This Is An X-Ray Of A Pregnant Dog

November 10, 2009


x-ray of pregnant dog with puppies in the womb

x-ray for 
pregnet dogPregnancy diagnosis

  1. Ultrasound scans. From day 21 to day 28, counting from the first coitus, it is possible to confirm gestation through an ultrasound scan diagnosis. It's much recommended.
  2. X-rays. A week before your dog gives birth, approximately day 51 counting from the first day, an X-ray should be made to confirm the number of fetuses, and at the same time, know their position. The x-ray should not be performed before day 51 since it could affect fetal development. Naturopathy

Can you see the nine puppies in the x-ray above?
The skulls look like squished circle outlines and the spines look like stretched out springs.

This x-ray was taken two days before the puppies were born. The right side of the picture is her tail end. Her spine is at
the top. Notice the hip bones?

Nine puppies is a large litter for a Soft Coated Wheaten Terrier. Bigger dogs usually have bigger litters. It is sometimes
easier for the mother dog if she has a big litter, because the pups tend to be smaller. But then she has to have enough
milk stations and patience to care for them after that.


Pregnant Dams spend a lot of their time in the last week stretched out, to get those puppies into position - Courtesy of MistyTrails Havanese

X-ray showing three puppies

X-ray showing three puppies

X-ray showing four puppies

This is a closeup up the puppy in the above picture who is in the process of being born. Note you can clearly see the puppy's front leg and head visible through the membrane.

The Whelping Cycle
Here is a chart which demonstrates
the process from mating to whelping
and puppy development.



A Breeder (with a capital B),
is one who thirsts for knowledge
and never really knows it all,
one who wrestles with
decisions of conscience,
convenience, and commitment.

A Breeder is one who sacrifices
personal interests, finances,
time, friendships,
fancy furniture,
and deep pile carpeting.

She gives up the dreams
of a long, luxurious cruise
in favor of turning that
all important show
into this year's "vacation".

A Breeder goes without sleep,
but never without coffee,
in hours spent planning
a breeding or watching anxiously
over the birth process, and afterwards,
over every little sneeze, wiggle or cry.

A Breeder skips dinner parties
because that litter is due
or the babies have to be fed
at eight.

She disregards birth fluids
and puts mouth to mouth
to save a gasping newborn,
literally blowing life into
a tiny, helpless creature
that may be the culmination
of a lifetime of dreams.

A Breeder's lap is a marvelous place
where generations of proud
and noble champions
once snoozed.

A Breeder's hands
are strong and firm
and often soiled,
but ever so gentle and sensitive
to the thrusts of a puppy's wet nose.

A Breeder's back and knees
are usually arthritic
from stooping, bending, and sitting
in the birthing box,
but are strong enough to enable
the breeder to show the next choice pup
to a Championship.

A Breeder's shoulders are stooped
and often heaped with abuse from competitors,
but they're wide enough
to support the weight of
a thousand defeats and frustrations.

A Breeder's arms are always able to wield a mop,
support an armful of puppies,
or lend a helping hand to a newcomer.

A Breeder's ears are wondrous things,
sometimes red ~ from being talked about ~
or strangely shaped ~
from being pressed against a phone receiver,
often deaf to criticism,
yet always fine-tuned to
the whimper of a sick puppy.

A Breeder's eyes are blurred
from pedigree research
and sometimes blind
to her own dog's faults,
but they are ever so keen
to the competitions faults
and are always searching for
the perfect specimen.

A Breeder's brain is foggy on faces,
but it can recall pedigrees faster
than an IBM computer.

It's so full of knowledge that
sometimes it blows a fuse.
It catalogues thousands of good bonings,
fine ears, and perfect heads,
and buries in the soul,
the failures and the ones
that didn't turn out.

A Breeder's heart is often broken,
but it beats strongly with hope everlasting,
and it's always in the right place!

Oh, yes, there are breeders, and then,
there are Breeders ~

Author unknown

Reproductive System

In biological terms sexual reproduction involves the union of gametes - the sperm and the ovum - produced by two parents. Each gamete is formed by meiosis (see Chapter 3). This means each contains only half the chromosomes of the body cells (haploid). Fertilization results in the joining of the male and female gametes to form a zygote which contains the full number of chromosomes (diploid). The zygote then starts to divide by mitosis (see Chapter 3) to form a new animal with all its body cells containing chromosomes that are identical to those of the original zygote (see diagram 13.1).

Diagram 13.1 - Sexual reproduction

The offspring formed by sexual reproduction contain genes from both parents and show considerable variation. For example, kittens in a litter are all different although they (usually) have the same mother and father. In the wild this variation is important because it means that when the environment changes some individuals may be better adapted to survive than others. These survivors pass their superior genes on to their offspring. In this way the characteristics of a group of animals can gradually change over time to keep pace with the changing environment. This survival of the fittest or natural selection is the mechanism behind the theory of evolution.

[edit] Fertilisation

In most fish and amphibia (frogs and toads) fertilisation of the egg cells takes place outside the body. The female lays the eggs and then the male deposits his sperm on or at least near them.

In reptiles and birds, eggs are fertilized inside the body when the male deposits the sperm inside the egg duct of the female. The egg is then surrounded by a resistant shell, laid by the female and the embryo completes its development inside the egg.

In mammals the sperm are placed in the body of the female and the eggs are fertilized internally. They then develop to quite an advanced stage inside the body of the female. When they are born they are fed on milk excreted from the mammary glands and protected by their parents until they become independent.

[edit] Sexual Reproduction In Mammals

The reproductive organs of mammals produce the gametes (sperm and egg cells), help them fertilise and then support the developing embryo.

[edit] The Male Reproductive System

The male reproductive system consists of a pair of testes that produce sperm (or spermatozoa), ducts that transport the sperm to the penis and glands that add secretions to the sperm to make semen (see diagram 13.2).

The various parts of the male reproductive system with a summary of their functions are shown in diagram 13.3.

Male repro ssystem labelled.JPG

Diagram 13.2. The reproductive organs of a male dog

Anatomy and physiology of animals Diagram 
summarising the functions of the male reproductive organs.jpg

Diagram 13.3 - Diagram summarising the functions of the male reproductive organs

[edit] The Testes

Sperm need temperatures between 2 to 10 degrees Centigrade lower and then the body temperature to develop. This is the reason why the testes are located in a bag of skin called the scrotal sacs (or scrotum) that hangs below the body and where the evaporation of secretions from special glands can further reduce the temperature. In many animals (including humans) the testes descend into the scrotal sacs at birth but in some animals they do not descend until sexual maturity and in others they only descend temporarily during the breeding season. A mature animal in which one or both testes have not descended is called a cryptorchid and is usually infertile.

The problem of keeping sperm at a low enough temperature is even greater in birds that have a higher body temperature than mammals. For this reason birds sperm are usually produced at night when the body temperature is lower and the sperm themselves are more resistant to heat.

The testes consist of a mass of coiled tubes (the seminiferous or sperm producing tubules) in which the sperm are formed by meiosis (see diagram 13.4). Cells lying between the seminiferous tubules produce the male sex hormone testosterone.

When the sperm are mature they accumulate in the collecting ducts and then pass to the epididymisbefore moving to the sperm duct or vas deferens. The two sperm ducts join the urethra just below the bladder, which passes through the penis and transports both sperm and urine.

Ejaculation discharges the semen from the erect penis. It is brought about by the contraction of the epididymis, vas deferens, prostate gland and urethra.

Anatomy and physiology of animals The testis 
& a magnified seminferous tubule.jpg

Diagram 13.4 - The testis and a magnified seminiferous tubule

[edit] Semen

Semen consists of 10% sperm and 90% fluid and as sperm pass down the ducts from testis to penis, (accessory) glands add various secretion

[edit] Accessory Glands

Three different glands may be involved in producing the secretions in which sperm are suspended, although the number and type of glands varies from species to species.

Seminal vesicles are important in rats, bulls, boars and stallions but are absent in cats and dogs. When present they produce secretions that make up much of the volume of the semen, and transport and provide nutrients for the sperm.

The prostate gland is important in dogs and humans. It produces an alkaline secretion that neutralizes the acidity of the male urethra and female vagina.

Cowpers glands have various functions in different species. The secretions may lubricate, flush out urine or form a gelatinous plug that traps the semen in the female reproductive system after copulation and prevents other males of the same species fertilizing an already mated female. Cowpers glands are absent in bears, dogs, and aquatic mammals.

[edit] The Penis

The penis consists of connective tissue with numerous small blood spaces in it. These fill with blood during sexual excitement causing erection.

[edit] Penis Form And Shape

Dogs, bears, seals, bats and rodents have a special bone in the penis which helps maintain the erection (see diagram 13.2). In some animals (eg the bull, ram and boar) the penis has an S shaped bend that allows it to fold up when not in use. In many animals the shape of the penis is adapted to match that of the vagina. For example, the boar has a corkscrew shaped penis, there is a pronounced twist in bulls and it is forked in marsupials like the opossum. Some have spines, warts or hooks on them to help keep them in the vagina and copulation may be extended to help retain the semen in the female system. Mating can last up to three hours in minks, and dogs may knot or tie during mating and can not separate until the erection has subsided.

[edit] Sperm

Sperm are made up of three parts: a head consisting mainly of the nucleus, a midpiece containing many mitochondria to provide the energy and a tail that provides propulsion (see diagram 13.5).

Anatomy and physiology of animals A sperm.jpg

Diagram 13.5 - A sperm

A single ejaculation may contain 2-3 hundred million sperm but even in normal semen as many as 10% of these sperm may be abnormal and infertile. Some may be dead while others are inactive or deformed with double, giant or small heads or tails that are coiled or absent altogether.

When there are too many abnormal sperm or when the sperm concentration is low, the semen may not be able to fertilize an egg and the animal is infertile. Make sure you dont confuse infertility with impotence, which is the inability to copulate successfully.

Sperm do not live forever. They have a definite life span that varies from species to species. They survive for between 20 days (guinea pig) to 60 days (bull) in the epididymis but once ejaculated into the female tract they only live from 12 to 48 hours. When semen is used for artificial insemination, storage under the right conditions can extend the life span of some species.

[edit] Artificial Insemination

In many species the male can be artificially stimulated to ejaculate and the semen collected. It can then be diluted, stored and used to inseminate females. For example bull semen can be diluted and stored for up to 3 weeks at room temperature. If mixed with an antifreeze solution and stored in straws in liquid nitrogen at minus 79oC it will keep for much longer. Unfortunately the semen of chickens, stallions and boars can only be stored for up to 2 days.

Dilution of the semen means that one male can be used to fertilise many more females than would occur under natural conditions. There are also advantages in the male and female not having to make physical contact. It means that owners of females do not have to buy expensive males and the possibility of transmitting sexually transmitted diseases is reduced. Routine examination of the semen for sperm concentration, quality and activity allows only the highest quality semen to be used so a high success rate is ensured.

Since the lifespan of sperm in the female tract is so short and ova only survive from 8 to 10 hours the timing of the artificial insemination is critical. Successful conception depends upon detecting the time that the animal is on heat and when ovulation occurs.

[edit] The Female Reproductive Organs

The female reproductive system consists of a pair of ovaries that produce egg cells or ova and fallopian tubes where fertilisation occurs and which carry the fertilised ovum to the uterus. Growth of the foetus takes place here. The cervix separates the uterus from the vagina or birth canal, where the sperm are deposited (see diagram 13.6).

Female repro system labelled.JPG

Diagram 13.6. - The reproductive system of a female rabbit

Note that primates like humans have a uterus with a single compartment but in most mammals the uterus is divided into two separate parts or horns as shown in diagram 13.6.

[edit] The Ovaries

Ovaries are small oval organs situated in the abdominal cavity just ventral to the kidneys. Most animals have a pair of ovaries but in birds only the left one is functional to reduce weight (see below).

The ovary consists of an inner region (medulla) and an outer region (cortex) containing egg cells or ova. These are formed in large numbers around the time of birth and start to develop after the animal becomes sexually mature. A cluster of cells called the follicle surrounds and nourishes each ovum.

[edit] The Ovarian Cycle

The ovarian cycle refers to the series of changes in the ovary during which the follicle matures, the ovum is shed and the corpus luteum develops (see diagram 13.7).

Numerous undeveloped ovarian follicles are present at birth but they start to mature after sexual maturity. In animals that normally have only one baby at a time only one ovum will mature at once but in litter animals several will. The mature follicle consists of outer cells that provide nourishment. Inside this is a fluid-filled space that contains the ovum.

A mature follicle can be quite large, ranging from a few millimetres in small mammals to the size of a golf ball in large animals. It bulges out from the surface of the ovary before eventually rupturing to release the ovum into the abdominal cavity. Once the ovum has been shed, a blood clot forms in the empty follicle. This develops into a tissue called the corpus luteum that produces the hormone progesterone (see diagram 13.9). If the animal becomes pregnant the corpus luteum persists, but if there is no pregnancy it degenerates and a new ovarian cycle usually.

Anatomy and physiology of animals Ovarian cycle
 showing from top left clockwise.jpg

Diagram 13.7 - The ovarian cycle showing from the top left clockwise: the maturation of the ovum over time, followed by ovulation and the development of the corpus luteum in the empty follicle

[edit] The Ovum

When the ovum is shed the nucleus is in the final stages of meiosis (cell division). It is surrounded by several layers of follicle cells and a tough membrane called the zona pellucida (see diagram 13.8).

Anatomy and physiology of animals An ovum.jpg

Diagram 13.8 - An ovum

[edit] The Oestrous Cycle

The oestrous cycle is the sequence of hormonal changes that occurs through the ovarian cycle. These changes influence the behaviour and body changes of the female (see diagram 13.9).

Anatomy and physiology of animals The oestrous 

Diagram 13.9 - The oestrous cycle

The first hormone involved in the oestrous cycle is follicle stimulating hormone (F.S.H.), secreted by the anterior pituitary gland (see chapter 16). It stimulates the follicle to develop. As the follicle matures the outer cells begin to secrete the hormone oestrogen and this stimulates the mammary glands to develop. It also prepares the lining of the uterus to receive a fertilised egg. Ovulation is initiated by a surge of another hormone from the anterior pituitary, luteinising hormone (L.H.). This hormone also influences the development of the corpus luteum, which produces progesterone, a hormone that prepares the lining of the uterus for the fertilised ovum and readies the mammary glands for milk production. If no pregnancy takes place the corpus luteum shrinks and the production of progesterone decreases. This causes FSH to be produced again and a new oestrous cycle begins.

For fertilisation of the ovum by the sperm to occur, the female must be receptive to the male at around the time of ovulation. This is when the hormones turn on the signs of heat, and she is in season or in oestrous. These signs are turned off again at the end of the oestrous cycle.

During the oestrous cycle the lining of the uterus (endometrium) thickens ready for the fertilised ovum to be implanted. If no pregnancy occurs this thickened tissue is absorbed and the next cycle starts. In humans and other higher primates, however, the endometrium is shed as a flow of blood and instead of an oestrous cycle there is a menstrual cycle.

The length of the oestrous cycle varies from species to species. In rats the cycle only lasts 4-5 days and they are sexually receptive for about 14 hours. Dogs have a cycle that lasts 60-70 days and heat lasts 7-9 days and horses have a 21-day cycle and heat lasts an average of 6 days.

Ovulation is spontaneous in most animals but in some, eg the cat, and the rabbit, ovulation is stimulated by mating. This is called induced ovulation.

[edit] Signs Of Oestrous Or Heat

  • When on heat a bitch has a blood stained discharge from the vulva that changes a little later to a straw coloured one that attracts all the dogs in the neighbourhood.
  • Female cats call at night, roll and tread the carpet and are generally restless but will stand firm when pressure is placed on the pelvic region (this is the lordosis response).
  • A female rat shows the lordosis response when on heat. It will mount other females and be more active than normal.
  • A cow mounts other cows (bulling), bellows, is restless and has a discharge from the vulva.

[edit] Breeding Seasons And Breeding Cycles

Only a few animals breed throughout the year. This includes the higher primates (humans, gorillas and chimpanzees etc.), pigs, mice and rabbits. These are known as continuous breeders.

Most other animals restrict reproduction to one or two seasons in the year-seasonal breeders (see diagram 13.10). There are several reasons for this. It means the young can be born at the time (usually spring) when feed is most abundant and temperatures are favourable. It is also sensible to restrict the breeding season because courtship, mating, gestation and the rearing of young can exhaust the energy resources of an animal as well as make them more vulnerable to predators.

Anatomy and physiology of animals Breeding 

Diagram 13.10 - Breeding cycles

The timing of the breeding cycle is often determined by day length. For example the shortening day length in autumn will bring sheep and cows into season so the foetus can gestate through the winter and be born in spring. In cats the increasing day length after the winter solstice (shortest day) stimulates breeding. The number of times an animal comes into season during the year varies, as does the number of oestrous cycles during each season. For example a dog usually has 2-3 seasons per year, each usually consisting of just one oestrous cycle. In contrast ewes usually restrict breeding to one season and can continue to cycle as many as 20 times if they fail to become pregnant.

[edit] Fertilisation and Implantation

[edit] Fertilisation

The opening of the fallopian tube lies close to the ovary and after ovulation the ovum is swept into its funnel-like opening and is moved along it by the action of cilia and wave-like contractions of the wall.

Copulation deposits several hundred million sperm in the vagina. They swim through the cervix and uterus to the fallopian tubes moved along by whip-like movements of their tails and contractions of the uterus. During this journey the sperm undergo their final phase of maturation so they are ready to fertilise the ovum by the time they reach it in the upper fallopian tube.

High mortality means only a small proportion of those deposited actually reach the ovum. The sperm attach to the outer zona pellucida and enzymes secreted from a gland in the head of the sperm dissolve this membrane so it can enter. Once one sperm has entered, changes in the zona pellucida prevent further sperm from penetrating. The sperm loses its tail and the two nuclei fuse to form a zygote with the full set of paired chromosomes restored.

[edit] Development Of The Morula And Blastocyst

As the fertilised egg travels down the fallopian tube it starts to divide by mitosis. First two cells are formed and then four, eight, sixteen, etc. until there is a solid ball of cells. This is called a morula. As division continues a hollow ball of cells develops. This is a blastocyst (see diagram 13.11).

[edit] Implantation

Implantation involves the blastocyst attaching to, and in some species, completely sinking into the wall of the uterus.

[edit] Pregnancy

[edit] The Placenta And Foetal Membranes

As the embryo increases in size, the placenta, umbilical cord and foetal membranes (often known collectively as the placenta) develop to provide it with nutrients and remove waste products (see diagram 13.12). In later stages of development the embryo becomes known as a foetus.

The placenta is the organ that attaches the foetus to the wall of the uterus. In it the blood of the foetus and mother flow close to each other but never mix (see diagram 13.13). The closeness of the maternal and foetal blood systems allows diffusion between them. Oxygen and nutrients diffuse from the mothers blood into that of the foetus and carbon dioxide and excretory products diffuse in the other direction. Most maternal hormones (except adrenaline), antibodies, almost all drugs (including alcohol), lead and DDT also pass across the placenta. However, it protects the foetus from infection with bacteria and most viruses.

Anatomy and physiology of animals Development 
& implantation of the embryo.jpg

Diagram 13.11 - Development and implantation of the embryo

Anatomy and physiology of animals Foetus and 

Diagram 13.12. The foetus and placenta

The foetus is attached to the placenta by the umbilical cord. It contains arteries that carry blood to the placenta and a vein that returns blood to the foetus. The developing foetus becomes surrounded by membranes. These enclose the amniotic fluid that protects the foetus from knocks and other trauma (see diagram 13.12).

Anatomy and physiology of animals Maternal and 
foetal blood flow in the placenta.jpg

Diagram 13.13 - Maternal and foetal blood flow in the placenta

[edit] Hormones During Pregnancy

The corpus luteum continues to secrete progesterone and oestrogen during pregnancy. These maintain the lining of the uterus and prepare the mammary glands for milk secretion. Later in the pregnancy the placenta itself takes over the secretion of these hormones.

Chorionic gonadotrophin is another hormone secreted by the placenta and placental membranes. It prevents uterine contractions before labour and prepares the mammary glands for lactation. Towards the end of pregnancy the placenta and ovaries secrete relaxin, a hormone that eases the joint between the two parts of the pelvis and helps dilate the cervix ready for birth.

[edit] Pregnancy Testing

The easiest method of pregnancy detection is ultrasound which is noninvasive and very reliable Later in gestation pregnancy can be detected by taking x-rays.

In dogs and cats a blood test can be used to detect the hormone relaxin.

In mares and cows palpation of the uterus via the rectum is the classic way to determine pregnancy. It can also be done by detecting the hormones progesterone or equine chorionic gonagotrophin (eCG) in the urine. A new sensitive test measures the amount of the hormone, oestrone sulphate, present in a sample of faeces. The hormone is produced by the foal and placenta, and is only present when there is a living foal.

In most animals, once pregnancy is advanced, there is a window of time during which an experienced veterinarian can determine pregnancy by feeling the abdomen.

[edit] Gestation Period

The young of many animals (e.g. pigs, horses and elephants) are born at an advanced state of development, able to stand and even run to escape predators soon after they are born. These animals have a relatively long gestation period that varies with their size e.g. from 114 days in the pig to 640 days in the elephant.

In contrast, cats, dogs, mice, rabbits and higher primates are relatively immature when born and totally dependent on their parents for survival. Their gestation period is shorter and varies from 25 days in the mouse to 31 days in rabbits and 258 days in the gorilla.

The babies of marsupials are born at an extremely immature stage and migrate to the pouch where they attach to a teat to complete their development. Kangaroo joeys, for example, are born 33 days after conception and opossums after only 8 days.

[edit] Birth

[edit] Signs Of Imminent Birth

As the pregnancy continues, the mammary glands enlarge and may secrete a milky substance a few days before birth occurs. The vulva may swell and produce thick mucus and there is sometimes a visible change in the position of the foetus. Just before birth the mother often becomes restless, lying down and getting up frequently. Many animals seek a secluded place where they may build a nest in which to give birth.

[edit] Labour

Labour involves waves of uterine contractions that press the foetus against the cervix causing it to dilate. The foetus is then pushed through the cervix and along the vagina before being delivered. In the final stage of labour the placenta or afterbirth is expelled.

[edit] Adaptations Of The Foetus To Life Outside The Uterus

The foetus grows in the watery, protected environment of the uterus where the mother supplies oxygen and nutrients, and waste products pass to her blood circulation for excretion. Once the baby animal is born it must start to breathe for itself, digest food and excrete its own waste. To allow these functions to occur blood is re-routed to the lungs and the glands associated with the gut start to secrete. Note that newborn animals can not control their own body temperature. They need to be kept warm by the mother, littermates and insulating nest materials.

[edit] Milk Production

Cows, manatees and primates have two mammary glands but animals like pigs that give birth to large litters may have as many as 12 pairs. Ducts from the gland lead to a nipple or teat and there may be a sinus where the milk collects before being suckled (see diagram 13.14).

Anatomy and physiology of animals reproduction 
Mammary gland.jpg

Diagram 13.14 - A mammary gland

The hormones oestrogen and progesterone stimulate the mammary glands to develop and prolactin promotes the secretion of the milk. Oxytocin from the pituitary gland releases the milk when the baby suckles. The first milk is called colostrum. It is a rich in nutrients and contains protective antibodies from the mother. Milk contains fat, protein and milk sugar as well as vitamins and most minerals although it contains little iron. Its actual composition varies widely from species to species. For example whales and seals milk has twelve times more fat and four times more protein than cows milk. Cows milk has far less protein in it than cats or dogs milk. This is why orphan kittens and puppies cannot be fed cows milk.


Pregnancy Determination in the Bitch

Jeanette L. Floss
College of Veterinary Medicine

Females of most domestic species are sexually receptive (in heat or estrus) every 17 to 21 days. Failure to return to estrus after a successful breeding is often the earliest indication of pregnancy in these animals. In the bitch, the average interval between periods of estrus is seven months, regardless of whether she becomes pregnant. Therefore, non-return to estrus is not a reliable indicator of pregnancy in the canine. Palpation and radiographic or ultrasonographic imaging of the abdomen are the most common methods of detecting pregnancy in the bitch.

Abdominal palpation

Palpation of the abdomen is included in any routine physical examination of the dog. This procedure allows the experienced examiner to feel normal as well as abnormal structures within the abdomen. While the dog is standing and depending on the size of the animal, one or two hands are used to palpate the abdominal organs.

The non-pregnant uterus may be difficult to identify. With pregnancy, the uterus enlarges and can be more easily palpated.

Embryonic vesicles can be felt as early as 20 days after ovulation. Usually evenly spaced within the uterus, these spherical swellings contain the developing embryos with their associated membranes and fluids. By 20 days after ovulation, the vesicles are approximately 1 centimeter in diameter. They are more easily identified in animals that are relaxed and are not overweight. Embryonic vesicles will increase in size until 32 to 34 days after ovulation, when they are no longer identifiable as individual swellings.

Because the uterus becomes uniformly enlarged, pregnancy is more difficult to determine by palpation. An abnormal condition (pyometra, mucometra, torsion) may develop that can also cause the uterus to be enlarged. Such a condition would need to be distinguished from a pregnant uterus.

Breeding behavior will differ between bitches and mating may take place from several days before to several days after ovulation. For this reason, intervals between breeding dates and expected pregnancy-related events can vary significantly (Table 1). Pregnancy can be determined by abdominal palpation during a relatively short period of time (20 to 32 days after ovulation). If breeding dates are used to estimate the stage of embryonic development, a second examination seven to 10 days after the first may be necessary to correctly identify a pregnancy. On the other hand, if the day of ovulation can be established, then the related gestational events can be more precisely timed (Table 1). Canine pregnancies range from 64 to 66 days and are similar in length for all breeds when measured from the time of ovulation.

Table 1
Approximate time of canine pregnancy events in relation to the time of ovulation and potential fertile matings (adapted from Concannon, P. W., 1986, p. 492).

Pregnancy-related event Number of days after ovulation Number of days after fertile mating
Onset of estrus -6 to +3  
First of multiple matings -7 to +5 -12 to 0
Fertile mating -5 to +5 0
Ovulation 0 -5 to +5
Fertilization 2 to 5 0 to 7
Vaginal cornification reduced 5 to 7 0 to 12
Embryo attachment to uterus 14 to 16 9 to 21
Vesicles visible with ultrasound 15 to 17 10 to 22
Palpable 1 centimeter swellings 20 to 22 15 to 27
Fetal heartbeat visible (ultrasound) 22 to 23 17 to 28
Uterine swelling visible on X-ray 28 to 30 23 to 35
Palpability of swellings reduced 30 to 32 25 to 37
Earliest X-ray pregnancy diagnosis 43 to 45 39 to 50
Fetal pelvis visible on X-ray 51 to 55 46 to 60
Fetal teeth visible on X-ray 56 to 61 51 to 66
Whelping 62 to 64 57 to 69

Ovulation is estimated to occur five to six days prior to the first day of diestrus. Diestrus is the stage of the reproductive cycle that immediately follows estrus. The first day is characterized by a dramatic change in the cells that line the vagina. Daily vaginal cytology examinations throughout estrus will help to identify when this change occurs.

In addition to vaginal cytology, ovulation can be estimated by measuring serum progesterone levels. Serum levels are low prior to estrus, but elevate sharply approximately two days before ovulation. For our purposes here, ovulation will be considered as Day 0 (zero). Additional pregnancy-related events will be described in terms of the number of days since ovulation.


Radiographic imaging (X-ray) of the abdomen is most accurate for determining pregnancy during the last trimester (43 to 63 days after ovulation). After 42 days, the fetal skulls and spines are visible on radiographs. As pregnancy advances, the bones of the front legs become visible, followed by the bones of the rear legs, the pelvis and the ribs. Finally, the fetal teeth become visible around 56 to 61 days after ovulation.

Prior to 40 days, the enlarging uterus may be visible on radiographs, but it may appear very much like the surrounding intestines. The contents of the pregnant uterus may be difficult to distinguish from an abnormal non-pregnant uterus before fetal skeletons develop. The physical and medical condition of the bitch will help to identify a diseased or a healthy pregnant uterus.

As the pregnancy nears its end, the number of fetuses can be determined radiographically by counting fetal skulls. Brachycephalic breeds (English bulldogs, Boston terriers, boxers, etc.) have an increased risk for difficult deliveries due to the size and shape of the fetal skulls. Radiographic evaluations late in pregnancy will determine if the fetuses are developed sufficiently (teeth visible) to survive and whether or not a cesarean section should be performed.


Ultrasonography is the application of high-frequency, low-intensity sound waves to various regions of the body. For the diagnosis of pregnancy, these sound waves are transmitted into the tissues of the abdomen. Different tissues reflect the waves back to the ultrasound machine, which then creates a 2-dimensional gray and white picture of the abdominal contents on a screen.

For this procedure, the bitch is placed on her back. The belly hair must be removed. A water-based gel is applied and the ultrasound transducer (probe) is then positioned on the belly wall.

Unlike radiographs, the contents of the uterus, whether normal or abnormal, may be identified. Fluid-filled structures will appear black on the ultrasound screen. Embryonic vesicles can be visualized 15 to 17 days after ovulation. They appear as black circles, approximately 1 millimeter in diameter within the gray walls of the uterus. By 19 to 20 days after ovulation, the vesicles are approximately 3 millimeters in diameter. If the uterine wall is included in the measurement, the vesicle will measure 1 centimeter in diameter. An accurate count is not always possible because some vesicles may not be seen and others may be observed more than once during the examination.

Ultrasonographic examinations commonly will be performed 24 to 30 days after ovulation, when fetal masses and heartbeats (120 to 150 beats per minute) can be visualized within the vesicles. With the ultrasound, fetal heartbeats are visible from 22 days after ovulation through the end of pregnancy. Heartbeats are often used to evaluate fetal life when complications arise during a delivery.


Progressive events of pregnancy are listed in Table 1. The earliest that pregnancy can be detected in the bitch is 15 to 17 days after ovulation. An ultrasonographic examination is required at this stage. By 28 days after ovulation, uterine swellings can be palpated or visualized on radiographs. An ultrasonogram at this stage would identify vesicles with embryonic tissue masses and heartbeats. After 32 days, palpation is of limited value in determining pregnancy in the bitch.

Ultrasonography also is beneficial for distinguishing between abnormal uterine conditions and pregnancy. Radiographic examinations are most useful during the last trimester of pregnancy, when fetal development can be evaluated and fetal numbers can be determined.

Pregnancy Symptoms in Dogs

Gestation is the period from conception to birth. It averages 63 days from the day of ovulation (the normal range is 56 to 66 days). Note that the day of ovulation is not always the same as the day of breeding.

During the first few weeks of gestation there are few signs of pregnancy, except for a slight gain in weight. Occasionally a bitch may experience morning sickness. This usually happens during the third to fourth week of pregnancy, and is caused by the effects of progesterone, combined with the stretching and distention of the uterus. You may notice that your bitch appears apathetic, lacks appetite, and may vomit from time to time. Morning sickness lasts only a few days. Unless you are particularly attentive, you may not notice it at all. If vomiting occurs, feed several small meals spaced throughout the day.

By day 40, the nipples begin to darken and enlarge, and the belly is increasing in size. As birth approaches, the breasts enlarge and a milky fluid may be expressed from the nipples. (Note that many bitches have breast enlargement after a normal heat period, so this alone should not lead you to conclude she is pregnant.)

Abdominal ultrasonography can detect puppies throughout pregnancy, beginning as early as 18 or 19 days after ovulation, although many veterinarians prefer to wait until 21 days for increased reliability. The technique is safe and effective, and does not use radiation.

The dog�s uterus has two horns that meet in a central uterine cavity. Developing puppies, encircled by their placentas, lie within the uterine horns. By palpating the abdomen, a veterinarian can tell by the 28th day after the last breeding whether a bitch is pregnant. The embryos can be felt as evenly spaced swellings about the size of walnuts in the average-size dog.

Abdominal palpation requires experience and a gentle hand. This should only be done by your veterinarian or an experienced breeder. There are other structures in the abdomen that may feel lumpy. Excessive poking and prodding can damage the delicate fetal-placental units and cause a miscarriage. If you would like to learn how to palpate for puppies, ask your veterinarian to demonstrate the procedure to you. After day 35, the fetuses are floating in capsules of fluid and can no longer be detected by palpation.

A blood test looking for relaxin levels can be done around 28 to 30 days of gestation. Relaxin is a hormone that increases during pregnancy. Another blood test in experimental development is for acute phase proteins. These are proteins that react to inflammation. In the case of canine pregnancies, the rise in these proteins is stimulated by the attachment of the embryos to the lining of the uterus (the endometrium).

Abdominal X-rays will show fetal bone structure at about day 45. X-rays are used as an alternative to ultrasonography, to distinguish among pregnancy, false pregnancy, and pyometra, and to estimate the size of the litter. X-rays should be avoided in early pregnancy, because the radiation could adversely affect the developing embryos before 45 days.

In late pregnancy, the abdomen becomes enlarged and pendulous. The movements of the puppies can be seen and felt during the last two weeks.


Prenatal Checkups

The first prenatal visit should be scheduled for two to three weeks after breeding. Any questions about activity and feeding during pregnancy can be answered at this time. Your veterinarian might schedule additional tests. Intestinal parasites, if present, should be treated.

Make an appointment to have the expectant mother seen again two weeks before her due date. Your veterinarian will want to discuss normal delivery procedures, alert you to potential problems, and give you instructions on how to care for the newborn puppies. Be sure to ask where you can get emergency service after hours, if it�s needed. At that time, you may want to have your bitch X-rayed to determine how many puppies you can expect.

If, for any reason, you suspect there may be problems with the pregnancy, you may want to look into a pregnancy monitoring system such as Whelpwise. These systems measure fetal heart rates and uterine contractions. The data you collect should always be discussed with your veterinarian before you attempt any treatment.


Gestation is the period when the young are developing in the mother�s uterus.  In dogs, gestation normally lasts 9 weeks (63 days).  However, puppies may be delivered between 58 and 68 days.

Diagnosis of Pregnancy   There are no practical blood or urine tests available to confirm pregnancy in the dog.  The earliest possible time of diagnosis may be 26-35 days after breeding, when the doctor may be able to detect pregnancy (85% accuracy) by feeling the abdomen.  Diagnosis by x-rays is usually possible after 45 days (95% accuracy for determining the number of puppies).

Physical Changes   During the first 5 weeks of pregnancy, there are few noticeable changes.  After the 5th week, you may notice weight gain, especially with large litters.   If only 1 or 2 pups are present, the mother may gain little weight until shortly before birth.  Abdominal enlargement is generally obvious in the last 3 weeks.  The mammary glands may begin to enlarge as early as the 35th day, but usually development is not obvious until 45 days.  Milk may be present as early as 7-9 days before delivery, but usually it is not produced until 1-2 days before delivery.

Behavioral Changes   During pregnancy, the female dog  may show a change in behavior, especially in the last few weeks.  As the uterus enlarges with the developing puppies, your pet may become restless, seek seclusion and in the last few days, soil the house.  She may shred papers, blankets or bedding in an attempt at �nest building� in the last weeks.  During the last 2 weeks, your pet may become irritable and should avoid contact with small children.

Nutrition   Good nutrition is essential for healthy puppies and mothers.  During the first 4 weeks, nutritional needs change little, but feeding small amounts of high protein supplements, such as eggs, lean muscle meats (not pork) or liver is a good practice.  During the last 5 weeks, your dog�s nutritional needs nearly double.  Feed increased amounts of food in several small meals each day.  Fresh water should always be available, since fluid needs are greatly increased.  We recommend feeding puppy food through the end of lactation (nursing).

Exercise   Moderate exercise is the proper approach.  Neither forced rest nor strenuous exercise is a good idea.  Short periods of gentle play and short walks are good.


Preparations for whelping   Begin preparations for delivery of puppies before the female gives birth.  A whelping box should be provided for the mother to begin sleeping in to ensure birth of puppies in the area you have chosen.  This box should be relatively small, with sides 6-8 inches high to keep the pups from crawling out of the nest.  Place the box in a secluded yet familiar area of the home, away from the family traffic, to allow the mother solitude.  Newspapers make excellent bedding because they can be changed easily, are absorbent and can be shredded by the mother as she makes her �nest.�  If such materials as old quilts, blankets, rugs or towels are used, they must be washed frequently.  If you want to know more precisely when delivery is near, check the rectal temperature of the mother twice daily from the 58th day of pregnancy until labor begins.  Normal rectal temperature varies between 100.5 and 102F.  Within 24 hours before the onset of labor, the rectal temperature drops nearly 2 degrees.

Labor and Delivery   Labor in the female dog can be divided into 3 stages.  The second and third stages are repeated with the birth of each puppy.

Stage 1:  During the first stage, the mother seems extremely restless and very nervous, and often seeks seclusion.  She may refuse food even if offered her favorite treats.  This stage may last 6-24 hours.  This is a good time to exercise the mother to allow her to urinate and defecate.

Stage 2:  In the second stage, contractions and expulsion of the puppies begin.  Usually a small greenish sac of fluid protrudes first from the vulva.  This is followed by the puppy and its attached placenta.  The normal presentation of the puppy is nose first, stomach down.  About one-third of all puppies, however, are born hindquarters first.  This presentation is considered normal in the dog.  After delivery, the mother opens the sac, cleans off the pup, and severs the umbilical cord.  You may have to perform these functions for the mother (see Obstetric Care below).  Make sure the sac is removed from the puppy immediately if it is unbroken during delivery.

Stage 3:  The third stage of labor is the resting stage, which follows each delivery.  Mild contractions and delivery of the afterbirth occur in this phase.  This stage usually lasts 10-30 minutes, but it may range from a few seconds to a few hours.  Some mothers may deliver two pups close together and then have a prolonged resting stage.

NOTE:  During the stages of labor, the mother dog may need to go outside for urination/defecation.  Be sure to follow her in case she has a puppy delivered while she is outside.  Also, dogs often give birth to puppies while standing, sitting, or laying down.  If everything appears normal, LEAVE THE MOTHER DOG ALONE.  Noise and movements often distract the dog so that she does not concentrate on delivering and/or nursing the pups.

Obstetric Care   After a pup is delivered, remove all membranes covering the puppy, clean the face, and remove mucus from the mouth and nose.  Rub the puppy with a clean towel to dry it and to stimulate respiration and circulation.  After a few minutes of rubbing, the puppy should begin to squirm and cry loudly.  The umbilical cord should be tied about an inch from the puppy�s body with fine thread and then cut on the side of the knot away from the puppy.  Apply a drop of iodine to the cord end after it is cut.

Assisting with the Birth   If a puppy seems to be lodged in the birth canal and the mother cannot expel it, rapid assistance is necessary.  There may not be time to call your veterinarian and drive to the hospital.  Grasp the puppy with a clean towel and exert steady, firm traction.  Do not jerk or pull suddenly.  The direction of the pull should be in a gentle, downward arc.  Traction may be applied for as long as 5 minutes.  If you cannot remove the puppy, call the doctor.

Behavior of the Mother   During whelping and nursing, your pet may not be her usual self.  She may be very nervous and filled with a sense of protectiveness for her new family.  Any aggression she may exhibit usually fades as time passes.

Notify the Doctor if Any of the Following Occur:

         You cannot remove a puppy lodged in the birth canal.

         There is strong, persistent labor for 30 minutes up to 2 hours without delivery of a pup.

         There is weak, intermittent labor for 6 hours without delivery of any puppies.

         It has been more than 4 hours since the last birth and it is probable that more puppies are still inside.

         There is a greenish-black discharge and no labor or puppies within 3-4 hours.  The greenish-black color is normal, but such a discharge should be followed very soon by the delivery of the pups. 

         The pregnancy lasts more than 65 days.

         If excessive panting or vomiting occurs, or if uncontrollable tremors develop, notify the hospital.


1.      The mother and offspring should be brought to the hospital within 24 hours of delivery for examination by the doctor.  This is to ensure that mother and offspring are healthy, all of the pups have been delivered, and there is enough milk supply.  Usually, a hormone injection is given to help with milk let-down and contraction of the uterus.

2.      Fresh, clean water should be available at all times.  We recommend feeding �puppy food� to dogs for the higher energy and protein level.  Feed the mother dog as much as she can eat.

3.      Try to keep the new family in quiet surroundings and avoid all commotion possible for the first two weeks.  Excitement can cause a lot of the problems that are seen in both the female and the offspring.

4.      Females will often have soft stools for a few days due to diet changes, vaginal discharges, and cleaning the offspring.  A vaginal discharge and the passage of blood clots is to be expected for a few days.  The discharge should not be greenish-yellow or have a bad odor.  Notify the hospital should the discharge persist for more than 7 days.

5.      Palpate the breasts and observe the nipples daily.  Wash with warm water if needed.  Notify the doctor of any discoloration in the skin, tenderness, or severe engorgement that occurs.  Watch for sores on the nipples as the puppies begin to get teeth.  Trim the puppies� nails if they are scratching the mammary glands.

6.       Food quantity may be decreased at �weaning� (about 4-5 weeks of age) to help decrease milk flow.

7.      Notify the hospital if the mother dog exhibits a change of disposition, nervousness, tremors, moderate weight loss, lethargy, or lack of appetite.

8.       If you decide to spay your pet, the best time is after the puppies are weaned and milk production has ceased, but before the next heat period.

9.      Normally the mother dog experiences heavy coat shedding (�blowing her coat�) during the nursing period.  Brush her regularly and call the doctor if any bald spots develop.

10.  Pregnancy should have no effect on the next heat period.  This period should occur within 6 months after the birth of the puppies.

11.  The mother dog needs to stay on heartworm preventive for the duration of pregnancy and lactation.  The heartworm preventive causes ABSOLUTELY NO HARM to the developing or nursing pups.

Canine Pregnancy Diagnosis


p 73-77


Abdominal Palpation

  • If the bitch is at a stage of gestation which enables it, abdominal palpation can be used to diagnose pregnancy. 

  • Some skill and care are required to adequately perform uterine palpation in the pregnant bitch.


  •  It is usually best to use one hand to palpate most dogs. 

  • The abdomen is palpated from the hepaxial muscles downward, attempting to slip the uterus between the thumb and fingers. 

  • In smaller dogs, one finger can be placed in the rectum and used as a landmark for palpation.  

  • The non-pregnant uterus and the pregnant uterus before day 21 of diestrus is not reliably palpated in most dogs.

A contrast radiograph of a bitch's uterus in estrus
demonstrating how small it is. The faint black arrow is the cervix.

  • During pregnancy however, from day 21 to day 31 from the first day of diestrus, when the uterus slips between your thumb and fingers you can fell 'walnuts', which are the distinct gestational vesicles. 

  • These vesicles average 1.5-3.5 cm between days 28-32 of pregnancy.

Click on the movie icon, then right click on the movie or "Open It" and "OK" to see
Canine Abdominal Palpation

A photo showing the distinct gestational sacs.

A photo showing how the gestational sacs become confluent,
and therefore difficult to distinguish.
  • It is difficult to accurately count the number of fetuses and the viability of the pregnancy cannot be determined by abdominal palpation.  

  • Some dogs are too large to palpate and some tense the abdomen and make palpation very difficult. 

  • Some dogs carry the pregnancy more cranial, therefore making palpation more difficult. 

  • Mammary enlargement may also make palpation difficult. On very large dogs, you may try to palpate with two hands, but it is not the best way to palpate. 

  • After day 31 the gestational sacs become more confluent and lose their distinction. However, after day 50 the puppies may be palpated directly.


  • (Yeager et. al. AJVR 53, 1992)  

    • Gestational sacs are visible as early as 18-20 days past the LH peak. 

    • There is usually little doubt when the black, hyperechoic gestation sac is observed, that the bitch is pregnant.  

  • Ultrasound is more accurate than palpation at all stages than palpation or radiography. 

  • The presence of fetal heartbeat and fetal movement can accurately establish fetal viability. 

    • The heartbeat is normally first seen more than 23- 25d after the LH peak. Fetal movement is seen after day 34-36 past LH peak 28.

  • Predicting gestation duration from ultrasound measurements

  Less than 40 days More than 40 days
Gestational Sac Diameter

(GSD) cm


GA = (6 X GSD) + 20

GA = (15 X HD) + 20


Crown-Rump Length

(CRL) cm

GA = (3 X CRL) + 27


Head diameter

HD (cm)


GA = (15 X HD) + 20



Ultrasound Sector Scan of Canine Pregnancy at 25 days.

Click to see the structures identified.

Click on the movie icons below to see ultrasound videos.

Ultrasound 25 days

Ultrasound 49 days

Ultrasound 52 days

Ultrasound 55 days




  • Ultrasound is especially useful between days d 33-45, because it is too late to palpate and too early for radiographs. 

  • Counting the number of fetuses difficult, because you can never be sure if you are seeing another fetus when you move the probe, or if it is the same one. 

  • Small litters may make it more difficult for ultrasound to be used to diagnose pregnancy. 

  • Ultrasound has great value in obstetrical use in the determination of fetal viability. 

    • The normal heart rate in the fetus is 200 beats per minute. 

    • An increase or decrease in the fetal heart rate indicates fetal stress. 

    • The absence of a heartbeat indicates fetal death.



  • The fetal skeleton becomes opaque 43-46 days after the LH peak making radiographic diagnosis of pregnancy possible 45-48 d after LH peak. 

  • Bones become visible at different times (see Rendano, Current Veterinary Therapy VIII, Kirk, ed.); for example, teeth are visible approximately 4 d before birth.  

  • After 50 days you can count the number, estimate size, and estimate the position of fetuses.

  • At LSU we routinely do a radiographic 'puppy count' to determine how many pups there are. 

    • This makes the attendant at whelping much more aware if whelping is done, or if assistance is needed. 

    • No negative effects have been seen in fetuses that were radiographed during the latter stages of gestation. 

  • Fetal Death Signs of fetal death can be visible to the trained eye.  

    • An alteration of fetal skull bone alignment with overriding or extreme deformity is a sign of fetal death. 

    • Intra- or peri- fetal gas accumulations indicates fetal death.  

    • Abnormal fetal posture such as the "ball sign" which is the increased flexion or straightening of hind limbs.

Can you see the pregnancy in this radiograph? No one can. The bitch is pregnant, however the uterine enlargement which is visible cannot be definitively diagnosed as a pregnancy. It may be a pyometra.

On the original radiograph (the one you will see in lab), the fetal skeletons are actually visible. A radiologist could probably see them in this picture. Why did I waste your time putting this poor image in the notes?.......I worked too hard on it not to.

Maybe this is better!


  • Relaxin is first observed at 20-30 d gestation and is present for 30-60 d postpartum.  

  • A test is marketed by Symbiotics - ReproCHEK  

  • The test seems good, but you must buy 16-40 tests (depending on how many you run at once) for $240 (one year shelf life). If you only test dogs occasionally, then the price is pretty about ultrasound.

  • Witness Relaxin

    • 5 Tests/box

    • Room temperature storage

    • 10 minute running time

    • Cost $78/5 tests

    • The Pregnant Dog

      The average canine pregnancy lasts approximately 64 to 66 days. During the first two-thirds of her pregnancy, you will likely notice little change in your dog's appetite, appearance or activity level. During this time of the pregnancy, your dog will do best if fed her normal maintenance diet. Overfeeding early in pregnancy will usually result in fat deposits and does not help the growth of the developing puppies.

      During the last 3 to 4 weeks of pregnancy, rapid weight gain and mammary gland development typically occurs.

      This is the point in pregnancy when the puppies begin to rapidly develop and the expectant mother will need additonal calories to help the pups during this growth phase. By the end of pregnancy, your bitch's weight may increase by 15 to 25 percent. Slowly begin changing her diet from maintenance to pregnancy or puppy food during the last trimester.

      Another concern during the later stages of pregnancy is that the expectant mother's stomach cannot hold much food. All the space is being taken up by growing babies. Feed your dog several small meals throughout the day to provide adequate nutrition.

      Making sure your pregnant dog eats normally is very important. Pregnancy toxemia can develop if the dog does not eat adequately. Some bitches will lose their appetite just before going into labor and some may show a decrease in appetite early in pregnancy. Temporary appetite loss can be normal and have no impact on the mother or developing babies. However, prolonged
      anorexia is a problem and your veterinarian should be alerted.

      Though you may think your dog needs supplemental vitamins and calcium to help her growing babies, this is not true if she is fed a
      balanced diet. Supplementation can actually be detrimental to the puppies if done inappropriately. Consult your veterinarian before adding any supplements.

      Canine Birthing

      Most dogs whelp (give birth) without any complications. Difficulties in whelping are most common in toy breeds and breeds with short snouts and large heads (such as English bulldogs). Dogs of these breeds may require Cesarean section
      surgery if pups cannot be delivered vaginally (through the normal birth canal).

      Approximately one day before whelping, the level of progesterone in the blood, which has been high throughout pregnancy, falls to a level not seen since the dog first went into heat. Within 14 hours of this progesterone drop, there will be a fall in the dog's
      rectal temperature (normally around 100 to 102 degrees Fahrenheit; prior to whelping, the temperature may drop below 99 F). This temperature decrease is usually followed by labor within 12 to 24 hours.

      The Stages of Labor

      Labor consists of three different stages.

      Stage I begins with the first contractions of the uterus and ends when the cervix is completely open and ready for puppies to pass out through the birth canal. Owners cannot usually see the contractions, but your dog may exhibit panting, restlessness, vomiting, anorexia (loss of appetite) and nesting behavior. Stage I may last from 6 to 24 hours. It's best to keep the environment quiet for your dog so as not to further excite her. Little else can be done for these completely natural events of whelping.

      Stages II and III alternate with one another: Stage II ends with the delivery of a pup, whereas Stage III ends with the expulsion of the placenta. It may take between 15 minutes and 4 hours between the deliveries of one pup and his placenta and the next. You shouldn't be concerned unless pups have not passed for longer than 4 hours or if your dog has been actively straining to deliver a pup longer than 30 minutes with no success. Contact your veterinarian or your local emergency hospital immediately should this occur.

      They've Arrived!

      new mother should vigorously clean each puppy as he or she is born. This helps to remove placental membranes, dry each puppy from maternal fluids and stimulate the puppy to breathe. This will also stimulate the mother's nursing instincts. The mother will usually eat the pup's placenta; this is natural. Approximately 40 percent of puppies are born breech (rear legs first). This isn't a problem unless the mother is straining excessively with little change in the pup's position. Any deviation from the normal whelping process should signal you to seek immediate veterinary advice.

      Newborn Puppy Care 101

      Assuming that the new mother has cleaned her pup of his placental membranes, the pup should be clean and dry within minutes of delivery. Always check for a normal breathing pattern and call your veterinarian immediately if there seems to be a problem. If the mother is not cleaning her pups, free them of their membranes immediately and call your veterinarian.

      The environment that a newborn puppy is to be reared in should be set up well in advance of whelping. A whelping box should be placed in an area of the house that allows your dog and her puppies much privacy. The box should have walls tall enough to allow the mother � but not puppies less than 4 weeks of age � to exit. It should be made of a material that can be easily cleaned. Non-vertical sides (sides that slant outward) are often recommended so pups don't hurt themselves or one another as they try to climb the walls of their enclosure.

      A heat source should be present since newborn puppies cannot regulate their body temperature very well. Environmental temperature should remain around 86 to 90 F during the first week of the puppy's life and gradually fall to 75 F over the next 3 weeks. The ideal humidity in the whelping box should be 55 to 60 percent. Drafts must be avoided.

      Very soon after birth, puppies should begin suckling from the mother. Newborns have very low reserves of energy, so they must obtain fresh reserves from the milk. In addition, since very few antibodies come from the mother through the placenta (blood) before whelping, puppies must get infection-protecting antibodies from their mother's first milk. However, if puppies don't ingest the milk within 12 to 16 hours after birth, very few antibodies will be absorbed and the puppy will be susceptible to infections until he can produce his own antibodies after 4 weeks of age.


      Normal Labor and Delivery in the Dog

      By: PetPlace Veterinarians

      The normal gestation period for a dog is 63 days.The normal gestation period for a dog is 63 days.

      Be Prepared

      Giving birth can be a frightening, confusing and painful experience for both the dog and the owner. Knowing and understanding normal labor and delivery, as well as proper pregnancy care, can help make the process go more smoothly and help you know what is normal and when it is time to get the veterinarian involved.


      In the bitch, a female dog, gestation lasts 63 days. Knowing the exact time of conception, however, is difficult since a bitch can be receptive to the male before and after ovulation. For this reason, the time from breeding to delivery is usually somewhere between 58 to 70 days. Your veterinarian can help narrow this time frame by examining the cells of the vaginal wall.

      Be aware that just because your bitch bred does not mean she is pregnant. Some dogs will even show signs of pregnancy and not really be pregnant. There is a phenomenon in dogs known as false pregnancy or pseudocyesis. For confirmation of pregnancy, an examination, with ultrasound and possibly X-rays by your veterinarian, is suggested.


      Once pregnancy is confirmed, proper care of the mother-to-be is very important. Before breeding, make sure she is up to date on all her vaccinations. It is not recommended to vaccinate your dog during pregnancy. Also, make sure she is dewormed and tests negative for a bacteria known as Brucella. This bacteria can cause abortion in dogs and is also contagious to people.

      After breeding and conception, most bitches do well during the first 4 to 5 weeks of pregnancy and do not need any special treatments. Things start to change during the last trimester (week 5 to 6). The babies start to rapidly develop and this results in a significant nutritional drain on the mother. At this time, you may want to consider gradually changing her diet to a growth type diet or a food specifically made for pregnant or lactating bitches. Continue this diet throughout the remainder of pregnancy and until the puppies are weaned. Vitamins or other supplements are not recommended nor needed. With a proper diet, your dog will receive the proper amount of nutrients. Excessive amounts can actually result in birth defects.

      Do not begin feeding your dog a higher calorie food before the last trimester. This can lead to weight gain and fat deposits. This has the potential to cause difficulty in maintaining the pregnancy and can result in problems delivering the puppies.

      Preparing for Delivery

      As the time of delivery approaches, you may want to make a whelping box to provide a safe and clean area for your dog to deliver. Whelping boxes are intended to be easily accessed by the mother but escape proof for the new arrivals. You can use wood, Formica or any building material that is easy to clean. Make the box large enough for the bitch to comfortably stretch out. Make sure the sides are just low enough for the mother to step over and place the box in a warm, dry, draft-free area. If possible, try to choose a quiet and secluded area. Initially, place newspapers on the bottom of the box for easy clean up. Once all the puppies are born, place blankets or towels to provide some footing for the puppies. Be aware that you must get the bitch used to the whelping box before the birth. If not, she may make her own decision on where to have the puppies � and this may be a closet, a pile of fresh clean laundry or even in the middle of your bed!

      An additional suggestion is to have your dog examined by a veterinarian toward the end of pregnancy. A thorough physical exam, along with ultrasound or X-rays can help determine how many puppies you can expect. This way, you will know when she is done delivering and not just in another resting phase between pups.

      Be Prepared

      Labor and Delivery

      As the time of delivery approaches, twice daily monitoring of the bitch's body temperature will help alert you to the impending birth. About 24 hours before the beginning of labor, there will be a temporary drop in the body temperature. Normal temperature is 101 to 102.5 degrees Fahrenheit. Twenty-four hours prior to labor, the temperature can drop to 98 to 99 F.

      Labor Stage I

      After the temperature drop, stage I labor begins, characterized by restlessness and anxiety. You may notice panting, pacing, refusal of food and maybe vomiting. Nesting behavior begins. This is the time to place her in the whelping box (hopefully she is already accustomed to the box). After getting settled in the whelping box, you may notice her dragging clothing or fabric to the area to form a comfortable bed. You may want to remove any clothing as whelping begins or these pieces of clothing may be permanently stained.

      This stage of labor typically lasts 6 to 12 hours. At the end of stage I, the cervix is completely dilated. If your dog has not started whelping within 24 hours after beginning stage I labor, veterinary assistance is recommended.

      Labor Stage II

      Stage II labor is defined as the part of labor when the puppy is delivered. Visible contractions begin. The abdomen tenses and the bitch begins straining. This action will appear similar to the bitch trying to have a bowel movement.

      The first puppy should be delivered within 1 to 2 hours of the onset of contractions and straining. Veterinary assistance is strongly encouraged if the first puppy is not delivered within 2 hours after the onset of contractions.

      After delivery of the puppy, the bitch may enter a resting phase that can last up to 4 hours. Active straining will begin again and more puppies will be delivered. If you know there are additional puppies yet to be born and the resting period is longer than 4 hours, veterinary assistance is necessary. This resting phase may not occur after each delivery. Sometimes, several puppies may be born rapidly.

      Labor Stage III

      After delivery of a puppy, the bitch may enter stage III labor. This is the time when the placenta, after birth, is delivered and usually occurs 5 to 15 minutes after delivery of the puppy. If multiple puppies are born rapidly, several placentas may be expelled together. After the passage of the placenta, the bitch will return to stage II labor. She may continue the resting phase or begin contracting. Throughout whelping, the bitch will fluctuate between stage II and stage III labor until all the puppies are born. It is very important to keep track of the number of placentas. There should be the same number of placentas as puppies. If a placenta is retained in the uterus, the bitch will eventually become quite ill.


      As soon as the puppy is born (whelped), the mother should immediately start cleaning the puppy. She should begin vigorously licking the puppy, remove him from the amniotic sac if still present and chew the umbilical cord. The bitch may even ingest the placenta. This is not necessary and, sometimes, can lead to vomiting and diarrhea. Prompt removal of the placentas can help you keep track of how many placentas she has passed.

      Those puppies that are born still in the sack need immediate help. If the mother does not open the sack and begin cleaning the puppy, it is up to you to help. Tear the membrane of the sack and begin cleaning and rubbing the puppy with a clean dry towel. Cleaning other puppies may be necessary if the mother is not showing much interest in her newborns. Tie off the umbilical cord about 1 inch from the belly wall using string, thread or dental floss. Cut the cord off on the other side of the tie. Clean and rub the puppy vigorously until you hear crying. Place the puppy back with the new mom and make sure she allows the puppies to nurse.

      Being prepared to assist and understanding newborn puppy care is essential to help the mother and her babies through these first steps of life.

    Just Before Labor Begins:

    Pregnancy in dogs last approximately 63 days (56-69 days). Toy breeds may deliver a week earlier while large breeds often deliver later. Two weeks before your dog�s due date, begin to take its temperature at noon. Purchase a rectal or oral thermometer but use it rectally. You can lubricate it with margarine or KY jelly and insert it about an inch. Leave it in place for three minutes. Your dog�s temperature should be between 101 and 102.5 Fahrenheit. When the pet�s temperature drops below 100F she should deliver the pups in less than twenty-four hours.

    Stage One of Labor:

    During the first stage of labor the cervix begins to dilate and uterine contractions begin. These contractions are painful and perplexing to the dog. She will appear quite uncomfortable and restless - pacing, shivering and panting. She probably will not eat and she may even vomit. Some dogs whine persistently. Others occupy themselves building a nest. Uterine contractions, although occurring, are not as easy to see as in humans. This is the longest stage of labor. It generally lasts six to eighteen hours. By the end of this period the dog�s cervix will have completely dilated for the puppies to pass. During this period keep the mother�s environment quiet and calm. I usually shut them off in a darkened area such as the bathroom.

    Stage Two of Labor:

    During the second stage of labor, uterine contractions begin in force. As this stage progresses the placental water sacks break and a straw-colored fluid is passed. Placentas are expelled after each puppy or sporadically during labor. Pups usually appear every half-hour or so after ten to thirty minutes of forceful straining. As the pups deliver, the mother will lick the puppy clean and bite off the umbilical cord. It is important to let the mother do this, if she will, because through this process she bonds with her puppies and learns to recognize them as her own. The rough licking of the mother stimulates the puppies to breathe and improves their circulation. The mother will probably eat some of the afterbirths. If the bitch does not tear away the sac and lick the pups to stimulate respiration, the owner should tear the sac open, clear all fluid away from the pup's nose and mouth, and vigorously rub the pup to stimulate breathing.

    It is not uncommon, however, for the mother to take rests during labor and up to four hours can pass between some puppies. If more than four hours have passed without a puppy and you are certain more puppies are present take the dog to a veterinary hospital. Also seek assistance if the mother strains forcefully for over an hour without producing another pup. If you see the rear legs of a puppy protruding from the dog�s vagina you can assist the mother by gently pulling the puppy in a downward and rearward arcing motion. You must do this very gently because puppies are fragile and easily hurt. It is normal for many puppies to be born rear feet first or breach. When a mother dog is stuck in incomplete labor the first thing I do is administer oxytocin and calcium to stimulate uterine contractions. If the puppies are too big to pass through the birth canal or the oxytocin fails to induce successful labor, I perform a cesarean section on the dog.

    Stage Three of Labor:

    The concept of a third stage of labor is borrowed from human labor terms. It is a very indistinct period in dogs. Once all the puppies have been born the dog enters this third stage of labor during which time the uterus contracts fully, expelling any remaining placenta, blood and fluid.


    After thirty-two days of pregnancy the mother�s appetite will begin to increase. She should begin to eat about twice as much as she used to. When the puppies come and she is producing milk, her food consumption should be about three times as much as it was before her pregnancy.
    Purchase a name brand puppy chow to feed her with during these periods. If you do so, there is no need to give her supplements of any kind. There is no need to restrict the mother�s normal exercise but intensive exercise or work training should be curtailed.

    Around the forty-fifth day, bring the pet in to be examined by a veterinarian. At this time the vet
    will be able to palpate the puppies and give you an indication of how many to expect. If you need to know earlier, then have an ultrasound examination performed about the twenty-fifth day.
    Blood progesterone levels can be tested about day 34 to confirm pregnancy.

    The puppies will be born still covered by their amniotic membrane. This membrane must be removed from the puppy�s face in order for it to breathe. Most momma dogs are very attentive to the newborn puppy and lick and tear the membrane off. If they are not or you just don�t have the patience to wait, assist the dog in doing this. Peel the membrane away and remove mucous from the puppy�s mouth and nose with a soft towel. Tie a piece of dental floss or thread around the umbilical cord about an inch from the puppy�s belly button and cut the cord distal to the knot.

    Serious Problems:

    If the mother fails to go into labor within twenty-four hours after her body temperature drops to below 100F you should take the dog to a veterinarian. Do this also if you have calculated that more than 69 days have passed since the dog was bred.

    Some dogs will suffer milk failure or insufficient milk before their puppies are weaned. This occurs in older dogs as well as dogs that have another concurrent health problem such as eclampsia, mastitis or systemic disease. These dogs need to be taken directly to a veterinarian the puppies supplemented or raised by hand. Signs that milk is inadequate are thin or lean puppies that cry consistently suck objects around them (or each other) and do not sleep.

    It is normal for the mother to run a low fever during the two days after giving birth. I become concerned if the fever is over 102.8, if the dog is drinking excessive water or if she is depressed. These may all be signs of a retained placenta (or puppy) or a uterine infection.

    It is normal for the dog to have a vaginal discharge following birthing. This discharge normally has rusty reddish or greenish brown appearance. I become concerned when the discharge is pus-like or has a strong odor. This can also be a sign of retained placenta and uterine infection (metritis). Normal cleansing of the uterus can last as long as eight weeks.

    Normal mother dogs are bright, alert and attentive to their puppies. She should have a ravenous appetite as she converts metabolites to milk. I become concerned if the mother shows any signs of listlessness or depression. She also needs to visit a veterinarian if she is not attentive to her puppies.

    Check the mother�s milk flow. It should flow with only the slightest of finger pressure.

    Eclampsia or Milk Fever:

    Eclampsia is actually a glandular problem in which the parathyroid gland does not secrete sufficient calcium-releasing hormone. When it does occur, this problem happens just before or within 3-4 weeks after welping. Milk fever is an acute, life-threatening condition. It is most common in small breeds with large litters. Mother dogs become disoriented, stiff, nervous and restless. They loose interest in her puppies. In severe cases they will have muscle spasms, seizures and be unable to walk. The mother may run a fever and have a rapid heart rate. . This problem results from low blood calcium as the mother�s body prepares to produce calcium-rich milk. I treat it by administering intravenous 10% calcium gluconate at 0.25-0.75ml/pound/hour. Affected dogs return to normal in fifteen minutes or less. Then I either wean the puppies or place the mother on a calcium supplement for the remainder of their lactation. Giving calcium supplements during pregnancy is not helpful and may actually cause the problem to reoccur during future pregnancies.

    Mastitis or Breast Infection:

    The normal canine breasts of mother dogs are soft, warm and enlarged. They should never be red, hot, painful and hard. Hard painful breasts are signs of infection. Dogs with this condition are reluctant to let the puppies nurse and when they do little milk is produced. As soon as I identify a dog with this condition I remove the puppies and hand feed them. Hot packs on the affected breasts help draw down the infection. I place the mother dog on antibiotics and limit her water supply to dry up her milk as quickly as possible.

    Hypoglycemia or Low Blood Sugar:

    This condition is easily confused with eclampsia. It is primarily a problem in small breeds. The signs are disorientation, weakness, subnormal temperature and low blood sugar analysis. I treat it by administering intravenous dextrose solution. Recovery is very rapid. I often give some dextrose at the same time I treat with intravenous calcium for eclampsia since the two problems often occur together.


    1. Pregnant dogs require special care just like pregnant humans. As a dog's pregnancy progresses, her nutritional needs change and her activity limitations expand. Moreover, preparation for labor and delivery must be made before the dog is ready to give birth to her puppies. For these reasons, it is important to determine what stage of pregnancy a dog is in, and to learn to recognize the symptoms associated with each pregnancy stage.


    1. Pregnancies in dogs are divided into four stages: stage one, stage two, stage three and imminent delivery. In the first stage, which lasts approximately three weeks, the pregnant dog will typically show no signs of being pregnant. However, some dogs in this stage of pregnancy may be reluctant to eat or may seem unusually tired. As the pregnancy progresses into the second stage, or weeks four through six, the dog's appetite begins to increase and she may begin to gain weight. Nipple growth typically begins at the beginning of stage two.

      Stage three symptoms include an obvious increase in abdominal growth and the beginning of milk production. The puppies may be felt moving in the abdomen during the end of stage three. This stage of pregnancy concludes near nine weeks. When delivery is imminent, the pregnant dog may begin nesting, appear restless and begin seeking a place to have her puppies. A temperature drop to 97 to 99 degrees F is a sign that delivery will occur within the next 24 hours.



    Time Frame

      While most dogs typically come into heat every six months, larger breeds may come into heat less frequently. Vaginal bleeding and swelling of the vulva are obvious signs that a dog is ready to breed. Once conception takes place, a dog's gestation period lasts for an average of nine weeks. Three weeks after breeding, or after the first stage of pregnancy, female dogs should be examined for signs of pregnancy Symptoms typically do not begin until the second stage, but dietary changes should be made if a pregnancy is suspected. The third stage of pregnancy begins near week six and lasts until a day or two before delivery begins. Because the time line of the pregnancy is important, and because pregnancy dating cannot be done until near delivery, the dates of breeding and symptom development need to be kept on record.


      Because pregnancies in dogs cannot be confirmed by urine or ultrasound until late in the pregnancy, knowing what symptoms and signs are associated with pregnancy in dogs can help tremendously in making the diagnosis. During the first month of pregnancy, most pregnant dogs will gradually begin to put on weight. This is especially true for dogs carrying many puppies. Generally, a diagnosis cannot be accurately made at all until nearly a month after breeding. At this time, the pregnancy may be detected by feeling the dog's abdomen for signs of developing puppies. X-rays can confirm the diagnosis and detect the number of puppies after approximately six weeks. About this time, mammary glands may also begin to enlarge, but milk may not be present until a week before delivery occurs.

    During the final few weeks of pregnancy, your dog may become irritable and should not be left alone with small children or other pets. As the birth gets closer, pregnant dogs often become restless, withdraw and may urinate or defecate in the house. Nesting typically takes place during the final week of pregnancy.


      There are some things to look out for in pregnant dogs, both during pregnancy and during the delivery process. If your pregnant dog stops eating and drinking, appears to be ill or begins bleeding during the first stages of pregnancy, she should been seen immediately by a veterinarian. During delivery, if a puppy becomes lodged in the birth canal, if strong labor persists for more than two hours without delivery of a puppy or if labor becomes weak, intermittent or lasts longer than six hours without giving birth, a veterinarian should be consulted immediately. Your pregnant dog should also be seen if her pregnancy continues beyond 65 days, and she should be seen in emergency care if she begins panting, vomiting or develops tremors.


    When will the puppies be born? Time for a canine pregnancy calendar...

    A canine pregnancy calendar is reviewed step-by-step in this article. Tips and advice are provided about handling and monitoring different stages of dog pregnancy.

    Starting with Conception

    Pregnancy for a dog is quite different than pregnancy for a woman and that is why a canine pregnancy calendar is a useful tool. For humans, a full term pregnancy takes about 9 months, give or take. However, for canines, the usual pregnancy period is about 2 months; typically 60 to 64 days.

    Not surprisingly, the pregnancy term depends on the breed of the canine. Small breeds start having heat cycles, known as estrus, when they are a mere 4 to 6 months old. With larger breeds, estrus starts at 12 to 24 months of age. Furthermore, heat cycles vary from dog to dog even within a certain breed. For example, some average 7 days, others for 10 days.

    Here�s another interesting fact. Unlike women, female dogs have menstrual cycles for their entire lives. Their reproductive systems do not stop regardless of age. Their periods never go away.

    Canine Pregnancy Calendar: Early in the Pregnancy

    If you�re trying to keep figure out the canine pregnancy calendar, you obviously need to take note of the day the dogs mated. After 48 to 72 hours, fertilization takes place in the oviducts. This is the trail from the ovaries to the uterus.

    After 10 to 11 days, the fertilized eggs will then become blastocytes and implant in the wall of the dog�s uterus. The blastocytes will grow into embryos. After 14 to 15 days, the dam�s nipples begin to get large and have a darker shade of pink. By the 20th day after conception, the fur on the dam�s belly and around the nipples will become thinner.

    From the 21st to the 28th day, the dam, just like a human female, may experience morning sickness. This is because of the hormonal changes she is experiencing and the stretching and distension of the uterus. The dam may lose its appetite and vomit once in a while.

    ===== Sidebar =====
    There are many reasons why a dog will stop eating. For example, they might be sick. Or, they might be getting food from another source. Some dogs even stop eating because they are eating poop!
    ===== Sidebar =====

    You can feed the dam several meals that are distributed through out the whole day to keep her healthy. Smaller meals are better than larger meals during the canine pregnancy calendar. On a related topic of canine pregnancy comfort, you can ask your veterinarian to prescribe a drug which relaxes the uterus. This isn�t necessary of course, but if your dog seems to be in pain it could be worth the effort.

    Canine Pregnancy Calendar: One Month Along

    After about a month of pregnancy, the dog embryos will be walnut sized and the breeder or veterinarian can determine how many puppies the dam is expecting. On the topic of health, you must begin to increase food rations to keep the dam healthy. At the same time, be very careful not over feed her because excessive weight gain can cause complications.

    At this point in the canine pregnancy calendar, the dam�s abdomen is large and is very visible that she is pregnant. The dam spends a lot of her time grooming herself. Her nipples also become even more swollen. She may be a little restless. She will be wandering about, sniffing one place and another and another. This is because she has started searching for a place where she can give birth to her puppies.

    Six weeks after conception, the dam may lose her appetite entirely. Her abdomen will be so big and hard because the puppies are already crowding one another. To keep the dam�s health and strength up, the owner must continue feeding her small meals that are distributed through the entire day. you can feel the puppies moving by touching the dam�s abdomen (if she�ll let you).

    Canine Pregnancy Calendar: Preparing for the Birth

    Almost two months after conception, you might want to clean the dam�s nipples and vulva by gently wiping it with a clean cloth and warm water. You can also trim the hairs surrounding the nipples so that the puppies won�t have a hard time sucking milk. At this point, milky fluid will come out of the nipples when they are squeezed.

    An indication that the dam is about to deliver is when her rectal temperature drops from 101 to 98 degrees. 12 to 24 hours after this, she will be delivering her puppies. Another sign is when there is a clear discharge from her vulva.

    The dam will also start whelping on the 59th to 64th day. Note that puppies that are born earlier than this period may not be able to survive. They are considered pre-mature.

    Canine Pregnancy Calendar: After the Birth

    Observe whether the dam is taking good care of her puppies. Some dams, especially if they are still too young, do not know how to tend to their young. Gently grab the puppies and slowly direct them to the dam�s nipples. Be gentle but firm with the dam. Insist that she remains in one location as the puppies feed.


    Like humans, dogs belong to a species that matures slowly after birth: the new-born is not completely developed and is incapable of surviving on its own. This implies a structured and caring parental environment (caring for the young), reflexes that orient the young puppy to its parents, and the existence of optimal, even crucial, periods in the development of the animal's nervous system.

    1. The growth of the nervous system underlies behavioral epigenesis. The immaturity of the nervous system at birth is obvious: Cragg (1975) calculated that in cats the number of synapses per cortical neuron grows from a few hundred to nearly 12,000 in the 10th to 35th day after birth (in Changeux, 1983). Various measurements (volume, weight, percentage of dry matter, oxygen consumption) of the brain show that growth is rapid until the 6-7th week when development suddenly slackens considerably. The number of brain cells and their myelination reaches full adult maturity at 4 weeks. It is worth mentioning that the brain is totally unmyelinated at birth, except for the trigeminal nerve and the non-acoustic part of the auditory nerve which correspond to the new-born's orientation reflexes (Herman 1958, in Scott & Fuller 1965). The motor cortex is the more developed at birth. The occipital cortex, however, then grows more rapidly than the motor and frontal lobes; it also contains several immature neuroblasts that reach full development only around 3 weeks of age (Fox, 1965).

    2. Behavioural epigenesis (ethogenesis) is linked to the way neuronal connections are organised (theory of selective stabilization). The development of the neuronal networks is a characteristic process: "the phase of synaptic redundancy followed by a phase of regression in the axonal and dendritic branches is a critical period of development... The redundancy is temporary. Active nerve endings are eliminated all the while the nervous system itself is expanding... This neuronal hecatomb is part of the normal development. ... The hypothesis that spontaneous, and later evoked, nervous activity contributes to the development of neural networks and synapses appears to be plausible" (Changeux, 1983).

    3. Behavioural epigenesis is influenced by environmental factors, by the surroundings. Activity regulates neuronal development. In a now classic experiment (by Weisel and Hubel from 1963, in Changeux 1983) with monkeys, noticeable visual defects were caused when one eye was sewn shut during the first six weeks of life; the problems were reversible if the eye was re-opened after three weeks' time. The same experiment on adult monkeys showed no effect on vision. Similar experiments on cats show there is a sensitive period for visual development between 3 and 7 weeks of age, and incapacity to recover vision after three months (Weisel and Hubel, in Vastrade, 1987). "There is a critical period during which the abnormal functioning of a system causes irreversible lesions." (Changeux, 1983). According to Klosovskii (1963), puppies and kittens that undergo periods of forced rotation for several days have vestibular neurons that are larger than those of animals that have not received this stimulus (in Fox: 1965).

      *In rodents, postnatal temporary occlusion of the ears leads to subsequent difficulties to locate sounds in space and to reduction of discrimination of auditive patterns (Caston: 1993). In rodents always, precocious exposition to other species odors eases future interspecific socialization (decrease in aggressions, lowering of corticostero�ds hormones) (Caston: 1993).

      * This reflects Cyrulnik's (1991) remarks that the brain becomes atrophied when [an animal] is raised in sensorial isolation, and it develops more than average in an environment of hyperstimulation in noise, affectivity, odors, tastes, sight, etc....

    4. Neurobiological studies have showed that prolonged precocious isolation was responsible for long-lasting structural or functional cerebral modifications. Isolation leads to a diminution of the dendritic network in the monkey frontal cortex; it also induces a reversible diminution of the activity of the mesocorticofrontal dopaminergic pathways (with hyperreactivity to stress), associated with a slight increase of the activity of the mesolimbic and nigrostriatal dopaminergic pathways (Verdoux and Bourgeois: 1991).

    5. Development thus seems to come about in stages; although these stages are possibly nothing more than a "simplified classification system where the classifier traces a straight line through a continuum" (Bateson, 1981). Pampiglione (1963) observed marked changes in EEG patterns at 7-8 days, 5-6 weeks (reaching adult levels), and 4-5 months (Fox, 1965). According to Charles and Fuller (1956) (in Scott and Fuller: 1965) the alpha rhythm that appears at 21 days signals an activation of the sense of sight. Scott (1958, 1962) (in Scott and Fuller: 1965, and Fox: 1965) speaks of several stages of neurological, reflexive and behavioral development that are particularly didactic: neonatal (0-14 days), transitional (14-21 days, starting when the eyes open and ending when the animal starts on hearing a noise), socialization (21-70 days) and juvenile (70 days and older). These periods overlap considerably. Since these stages are still used in the literature, they are worth mentioning. We recommend reading Vastrade (1986), Markwell & Thorne (1987), and Nott (1992) for an overview, or Scott and Fuller (1965) or Fox (1965) for a more in-depth study.

    In conclusion: behavioral patterns develop over successive phases, according to internal and external factors that interact in a complex and continuous manner. As Cyrulnik wrote, "the World of each animal is built around the double constraint of genetics and development".

    The Concept of Sensitive Periods

    Bateson (1981) has described the developing individual as a train with its windows closed - at a certain point (maturing) the windows open and the traveler is encouraged to study the information passing by outside. Depending on the information presented (learning), he/she either continues (motivation) or stops (habituation, impregnation, or self-limitation) looking out the open window. In other cases the windows close when a new point is reached.

    This notion of learning in phases has various names: sensitive period, critical moment, optimal period, vulnerable point, crucial stage, susceptible period, and so on.

    A sensitive period is a point in the maturing process when events are susceptible to leaving long-term effects, or a period when learning is easier and knowledge gained is stored in the long-term memory. During the sensitive period, a small number of determining experiences have major effects (or damages) on future behavior. The sensitive period is preceded and followed by periods of lower sensitivity, and the transition is gradual.

    The notion of sensitive period is used in the place of critical period because the former extends over a longer period of time. Ducklings become attached to their mother between the 13th and 16th hour of life (Hess 1959, in Cyrulnik 1989), it takes 5 minutes of contact during the first hour after birth for a she-goat to become attached to the odor of her kid (Bateson, 1981), and a ewe needs contact within 4 hours after the birth of her lamb. Without this contact the mother will reject her young in the last two cases (Collias, 1956, in Scott and Fuller, 1965). These very short periods justify the term critical. Since puppies do not have such short periods of facilitated learning, we will use the term sensitive period.

    I was one of the people who helped spread this concept in French-speaking countries (Dehasse and De Buyser: 1983, 1989, 1991) by emphasizing on several occasions that the sensitive period in the behavioral epigenesis in puppies extended from 3 weeks to 3 months of age. The duration of this sensitive period had to be verified by delving into the literature on experiments in this realm and clinical review.

    The Prenatal Period

    Pregnant rats that have been placed under stress or injected with ACTH or adrenaline give birth to young rats that are emotive and perform less well than a control group. (These young rats are raised by another mother that has not been placed under stress to preclude the possibility of postnatal maternal influence.) (Fox, 1978)

    In a similar vein, when a pregnant animal is petted her litter is more docile (Denenberg and Whimbey 1963, in Fox 1978). This effect, called the "gentling", "petting" or "caress" effect, can be prolonged by caresses to the new-born. According to Fox (1975, in Fox 1978) this activates the parasympathetic system, facilitating relaxation, digestion and emotional attachment, and thus socialization as well. Experiments by Cyrulnik with cats have shown that attachment depends on the cholinergic system; anti-cholinergics block the attachment process. The object of attachment is a being whose presence soothes and whose absence causes distress, who possess the signs of familiarization; a "reference being" (Eibl-Eibesfeldt 1984). This is probably linked to the social species' innate need for contact.

    A dog's tactile capacities develop before birth, and it is possible that it already becomes used to contact in the uterus, when the mother is petted. Puppies manipulated this way show a greater tolerance to touching than dogs born of a mother who was not petted.

    In rats, once again, manipulation (contact, exposure to cold, etc.) at a young age or before birth (manipulation of the pregnant mother) gives greater resistance to stress (cold, hunger) and disease (implanted tumors). This phenotypical effect is transmitted non-genetically for several generations (Denenberg and Rosenberg, in Fox 1978).

    These experiments enable us to deduce that when a gestating pet is given a friendly and caring human environment (with affectionate physical contact), the domestication and emotional balance of her offspring is facilitated, as compared with an environment where there is no contact and interaction with people.

    The Neonatal Period

    We will only say a few words about this period, which arbitrarily ranges from birth to the opening of the eyes at approximately 13 days.

    Eye opening at 8 days old (Golden Retriever puppy)Superficial, limited observation of the new-born puppy could lead one to believe it did not even belong to the canine species: awkward, dragging itself around, oriented to contact, the mother's teats and the smell of milk, yapping in distress when isolated, cold, hungry or in pain, and having only a limited capacity to keep itself warm and to learn. The new-born puppy is a completely dependent being, and apparently hardly influenceable psychologically in classical conditioning tests. As such this phase holds only minor interest in our study.

    It is possible, however, that the future holds surprising discoveries about the epigenetic importance of this neonatal period, especially as concerns the "manipulation" effect on neuro-hormonal development.

    The Identification Phase

    At birth the puppy has not an innate recognition of members of its species; in a way it does not know it is a dog. This must be learned!

    Through species identification a puppy is able to recognize its parents (filial imprinting), and develop preferential intraspecific social relations (fraternal imprinting) and the relations (sexual imprinting) which mean the survival of the species (filial and sexual imprinting). An animal that is badly imprinted is lost for the species.

    Here are a few examples:

    Christy, a female puppy, was raised in complete isolation from other dogs by the "colony" of students at the Jackson Laboratory. At 9 weeks she was introduced to other dogs: the adults growled at her but showed no further signs of aggression and the puppies (litter-mates) began to play-fight and she responded. In 4 days time her behavior was indistinguishable from that of the other puppies (Scott and Fuller, 1965).

    Note that, unlike goats and sheep, adult dogs show no parental rejection of their young!

    A fox terrier puppy (male) raised in complete isolation and introduced to other dogs at 16 weeks displayed inhibited behavior and was attacked by the other puppies that were normally socialized. He was placed with other dogs also raised in isolation; the dogs lived alongside each other, without aggression but also without interaction (Fisher, 1955 in Scott and Fuller, 1965). Dogs raised in isolation and placed in contact with others of their species at 16 weeks are attacked and rejected. When the experimenters mime play-fights against these same dogs, they are able to recover a positive dog-dog interaction and complete integration in the same pack within a few days (Fuller, 1961 in Scott and Fuller, 1965).

    Male chihuahuas raised by cats until 16 weeks of age demonstrate preference for the presence of cats, and submission - or fear - in the presence of dogs (they also show no reaction to their reflection in a mirror). When they are placed with other dogs at 16 weeks, they recover intraspecies socialization in two weeks; they now prefer dogs to cats and react to images of themselves in a mirror (Fox, 1971, in Pieters 1984).

    On the other hand, puppies raised in a family from 4 weeks of age (becoming used to dogs, cats and/or children), without renewed contact with the laboratory dogs, show greater familiarity with people than with dogs. An adult sheltie (who had lived with a cat and two children) showed sexual attraction for the cat and attacked all dogs (male and female alike); a beagle became "attached" to a vacuum cleaner bag; a basenji (who lived with a female dog) became a delinquent stray who attacked other dogs (Scott and Fuller, 1965).

    Clinical practice shows that when a puppy is acquired at 6 weeks this is already a handicap in developing its adult social and sexual preferences.

    We should also mention that the first signs of humping (pre-imitation of future sexual behavior) appear as early as 3 to 4 weeks (Scott and Fuller, 1965).

    This behavior is provoked by pressing on the sternum or the stomach. It is possible that this is a factor in sexual imprinting, but it has yet to be proven.

    To my knowledge, no statistical studies have been made on dogs raised in isolation, covering a broad range of breeds (for ethical reasons?), which means that crucial experimental data are lacking. Our knowledge is partially extrapolated from ethology studies in birds. Among birds, imprinting lasts throughout parental care and this period is shortened when there is a danger of mixing species. Preference is given to visual and auditory imprinting whose effects last almost a whole lifetime. With mixed imprinting, there is a preference (innate predisposition?) for one's own species over a neighboring species, and for this species over a more distant one (such as humans).

    In conclusion, species identification (filial, fraternal and sexual imprinting) is acquired during a sensitive phase of development, and depends on "play-fighting" among puppies (litter-mates). This begins about the third (3��) week and ends somewhere between 11 and 17 weeks (12�5), when the dogs loose their ability to play with unfamiliar dogs and become "serious" in defending their group. In the absence of siblings, a puppy establishes identification through care-giving, care-searching and/or playful interaction with its parents or other dogs. This interaction must last until at least, if not beyond, the 6th week. The presence of other species during this period does not hamper identification with one's own species.

    The end of this phase varies depending on factors that are internal (breed, line of descendants, individual) and external (behavior of the mother, other dogs, quality of the surroundings). A stressful environment (feral dog) will close this phase ahead of time (probably around 7 to 9 weeks).

    This type of learning presents several characteristics:

    • it is stable, rigid and persistent (sometimes for life);
    • it is easily acquired;
    • sexual imprinting occurs on supra-individual and supra-breed characteristics, which permits species generalization;
    • filial imprinting (attachment) seems to be more discriminating and is limited to parents;
    • fraternal imprinting is the basis of sociability;
    • attachment is an interactive process.

    Risk factors

    They are similar to those found among birds.

    The total absence of other dogs (own species) between 3 and 12�5 weeks fosters identification with another species that is closest (in general humans, but occasionally cats, rabbits, etc.) or an appropriate substitute (stuffed animal, vacuum cleaner bag, etc.). This identification is persistent, occasionally for life. In adults this leads to:

    • Courting behavior and attempts to copulate with the identification species (despite activation by pheromones of one's own species), no behavior of this type or else awkward attempts with a sexual partner of the same species,

    • Social preference for the identification species,

    • Rejection (flight or fight) of one's own species (including mirror images).

    The relative absence of other dogs between 3 and 12�5 weeks leads to relative, total or no handicaps depending on circumstances:

    • possible recovery of the dog's species identity at 9 weeks when it plays with other puppies,

    • attachment to the identification species and disinterest or aggression towards canines, despite the (almost) normal capacity to reproduce,


    The imprinting effects of a mirror placed in the surroundings of a puppy isolated from other puppies have not been studied (to my knowledge). Since no interaction is possible with a mirror image, this seems to be a poor substitute for suitable "imprinting".

    The Socialization-Domestication Phase

    A puppy is not programmed to interact socially with another species. Twelve thousand years of domestication, however, has shown that this is possible. The dog's particular nature - a puppy has to learn to identify its own species - can serve to foster socialization with other species (called domestication when it involves interaction with humans).

    Let's look at a few experimental cases:

    Puppies raised in a semi-open environment in (nearly) complete isolation from humans reacted differently towards an active unfamiliar observer depending on their age. Each puppy was taken from the surrounding in which it was raised, placed in contact with humans for one week, and again tested. Fear in the presence of a human that handled him decreased from 3 to 5 weeks, was minimal at 5 weeks, then increased again afterwards. "Recovery" (improvement or disappearance of fear) after a week of interaction-socialization was more efficient at 3 weeks; it was roughly the same at 5, 7 and 9 weeks (Freedman, King, Elliott, 1961, in Scott and Fuller, 1965).

    A puppy - raised in the same type of surroundings - was placed 10 minutes a day with a passive observer, calmly sitting in the room and paying no attention to the dog (Scott and Fuller, 1965):

    • at 3 to 5 weeks, the puppy investigated the observer openly;
    • at 7 weeks, it took 2 days before it investigated (2 10-minute sessions)
    • at 9 weeks, 3 days;
    • at 14 weeks it no longer investigated the observer.

    At 12 weeks a puppy is easily frightened. Confinement and hand feeding enable it to accept contact with its laboratory handler(s) but not with strangers, and it still prefers the presence of dogs to that of humans (Scott and Fuller, 1965).

    This fearful reaction has been found in all breeds tested. When put on the defensive a cocker's bite is "softer" than that of other breeds tested (basenji, terrier, beagle, sheltie).

    According to Fuller (1961), puppies raised in isolation in a laboratory develop adequate socialization to humans if they receive two 20-minute periods of human contact per week. This short contact, however, is not enough for basenji puppies; this variability is thus truly linked to breed (genetics) (Scott and Fuller, 1965).

    In conclusion, puppies demonstrate an investigation-attraction behavior towards the unfamiliar as soon as they are able to express this attraction (almost adult motor capacity), in other words at 3�� weeks. This attraction subsides in an almost linear manner after the fifth week until at least 9 weeks. The attraction recedes under the influence of fear of the unknown behavior which grows after 5 weeks; the puppy "recovers" from its initial fearful reaction instantaneously from 3 to 5 weeks (investigation behavior effect), and then it remains wary for longer periods as it grows older. At 12 weeks socialization requires active manipulation (mimicking play-fights), at 14 weeks socialization seems to be impossible.

    In birds fear of the unknown is delayed when they are raised in isolation; this phenomenon thus appears to depend on experience rather than maturing of the nervous system (McFarland, 1981) - one must first be able to refer to something "known" before fearing the unknown.

    An arbitrary limit can thus be set for spontaneous socialization to another species, during a first encounter, at 12 � 2 weeks. Nothing, however, enables us to affirm or deny that rapid habituation to close stimuli cannot be achieved after 12 weeks.

    Interspecies socialization (attachment) does not have the same characteristics as species identification:

    • It is easily acquired but requires permanent reinforcement to avoid de-socialization;

    • it is not generalized (generalisable) to all individuals of the species concerned, but remains relatively limited to the individual's characteristics. It is thus infra-species: it is a "type" socialization (human: man, woman, adolescent, child, baby, black, white, with/without beard, hat, white apron, etc.). The capacity to generalize varies from one species to another (dog and wolf, more than coyotes), breed (watchdogs less than other dogs, according to Fox, 1978), the family line and individual (no statistical studies available).

    • The threshold of socialization (number of interactions) is variable and depends on factors that are internal (breed, individual) or external (mother's fearful behavior, quality of the surroundings, etc.).

    Risk Factors

    Domestication depends on the presence of humans between 3 and 12 � 2 weeks in the surroundings in which a puppy develops and this socialization must be continued throughout the animal's life. The lack of human contact between 3 and 12 � 2 weeks fosters the development of fear/wariness of humans (feral dog).

    The relative absence of human contact leads to relative handicaps, such as fear/wariness/phobia towards a type of human (children, men,...).


    The interactive presence of different types of humans between 3 and 12 � 2 weeks facilitates a puppy's generalized socialization to humans.

    The interactive presence of other animals leads to interspecific socialization and attachment, and it counters predatory behavior.

    Interspecific socialization counters predatory behavior towards the type of attachment individual.

    The Emotional Self-Regulation (Homeostasis) Phase

    Homeostasis is the ability of an organism to maintain an equilibrium in a variable environment. Just as we have thermo-regulation (thermal homeostasis), we can also speak of emotional and relational homeostasis (Vincent, 1986). And we could even stretch the analogy somewhat: the organism has a thermostat for heat regulation, and a 'ponderostat' to maintain an ideal weight (Vincent, 1986). Likewise for emotional and relational homeostasis we could also envisage the existence of a "sensoriostat", "thymostat" or "sociostat" respectively measuring a being's sensorial perception, and emotional and social equilibrium.

    Living in a group and adapting to varied environments calls for a certain degree of emotional equilibrium (with minor fluctuations). This adaptation is possible only through habituation (disappearance of reactions) to certain stimuli. That this process is essentially learned, rather than genetically acquired is a sign of the species' ability to conquer - and adapt to - varied and new environments. This ability is an opportunity, but also a cause for risk.

    Among animals, innate fears do exist, although in dogs they remain to be demonstrated: for example the fear of "beating" or "gunshots" is not innate, despite various writings along these lines. Nonetheless, you can talk about acoustic sensitivity in individuals or breeds. This has been demonstrated in rodents: certain strains of mice (DBJ/2J) have shown an innate hypersensitivity to certain sound frequencies which give them convulsions (Dantzer, 1988).

    A large number of fears arise from an individual's development. Is there a sensitive phase during which it would be easier to establish emotional homeostasis, enabling the individual to develop frames of reference (referential, thymostat) and long-term habituation? The answer is "yes".

    Here are a few examples:

    A dog's typical reaction to an unfamiliar situation is fear: starting, fleeing or inhibition. In a semi-open milieu, the dog tends to flee (and is impossible to catch after the age of 4 months) (Scott and Fuller, 1965).

    w w When it is raised in isolation in a closed environment (0.2 m� cage) the flight reaction does not develop; instead only inhibition or fear-provoked aggression develop (Fisher, 1955; Fuller, Clark, Walker, 1960 in Scott and Fuller, 1965).

    If guide dogs for the blind are placed in a foster family at 12 weeks, they generally adapt well, but placement at 14 weeks can prove to hinder performance in later training (Scott and Fuller, 1965).

    Fox (1975) experimented with puppies placed in contact with increasingly complex stimuli (enrichment) at 5, 8, 12 and 16 weeks: as they grow the puppies tended to seek out complex environments. Puppies raised in surroundings poor in stimuli ("stimulus-poor puppies") and placed for the first time in a highly stimulating environment at 12 or 16 weeks are inhibited (fear) and search less complex environments. Enriched puppies are systematically dominant in the presence of stimulus-poor dogs.

    Male dogs are raised in normally lightened cages for the 10 first months of their life, but without any contact with the outside world (restricted sensorial situation). They are tested at 10 months old. Their activity level is 6 times higher than average dogs raised in normal surroundings (motor hyperexcitement). They learn slowly and forget easily (every trial is like a new experience). When they have learned some behavior, they reproduce it even when the rewarding factor has been removed (lack of the extinction process). Put in the presence of a bitch in oestrus, they show a state of increased excitement but they direct it towards stereotyped habitual behaviors and not towards the stimuli coming from the bitch. (Caston: 1993). For Caston, sensorial and social deprivation has impeached the maturation of the brain: it can not exert an inhibitory influence on the mesencephalic reticular formation (MRF) anymore; MRF is becoming hyperactive, and produces unfocalised and unadaptative behaviors. This has been verified by EEG recordings (in rabbits). In rhesus monkeys, this deprivation syndrome leads to high level of blood cortisol. *

    Stimulus-poor primates show a greater degree of attachment to their mother (pathological hyper-attachment), which led Bobbitt (1968, in Fox 1975) to propose that detachment from the mother is a continual process linked to a young being's attachment to the environment. This conclusion can most likely also be applied to dogs.

    In clinical practice we have observed dogs acquired at 3 or 4 months that had phobic behavior, whereas their siblings, acquired at 2 months, were emotionally balanced.

    I also participated in a study on the effects of a serotoninergic psychotropic drug on the behavior of beagles raised in a kennel. The beagles were chosen for their anxious-inhibited (depressive) behavior. In exactly identical conditions, with limited human contact (kennel staff) it was easy to choose 16 dogs of 8 - 13 months in which the following symptomatic behavior towards the presence of humans could be observed:

    -expectancy posture (Pageat, 1986) (locomotor inhibition, almost crouching, tail between the legs, head extended towards the stimulus presented),

    • refusing, or cringing from, hand contact,
    • lack of interest or catatonic immobility in the presence of a colored moving object,
    • inhibited movements outside the kennel (limited city noise).

    In this single-breed kennel (little variation in genotype) in a relatively deprived sensorial environment, there was a high degree of phenotype variation with, nevertheless, a large percentage (more than 50%) of dogs displaying inhibited behavior (more than 75% of the dogs were anxious). An overall inhibition index was established (4 tests each rated from 1 to 6, for a total ranging from 4 to 24 points, with 24 being the value for a normal dog).

    • At the start of the experiment, all the dogs tested between 4 to 10 points.
    • After 2 months they ranged from 8 to 21.
    • As the effects of the psychotropic drug were not significantly demonstrated compared to that of a placebo, the evolution towards 'normal' behavior could be imputed to the effects of the experiment itself, since the dogs were tested every other week (5 minutes maximum per dog) and given medicine twice a day.

    In conclusion: "industrial" kennel conditions suffice to cause anxiety and inhibition (undoubtedly favored in this case by the breed and enclosure in a 9m� cage). Nevertheless a mere daily contact, and handling every other week were enough to lower the level of inhibition and anxiety in this group of young adult dogs significantly.

    Indeed, the process of organizing stimuli from the outside world, classifying them as known or unknown, agreeable, disagreeable or indifferent (their "significance", meaning, socialization) is similar to the process of interspecific socialization. Eventually, this is merely one element in the acquisition of self-regulation as regards particular stimuli because they are interactive.

    We thus have a phase of facilitated spontaneous learning that begins with a dog's sensorial opening and investigation of stimuli (3 � � weeks) and ends when it develops fear of the unknown (12 � 2 weeks).

    The characteristics of this learning phase are the same as those of interspecific socialization (facilitated but requiring reinforcement, low level of generalization, etc.).

    The result is frames of reference acquired for each isolated or grouped sense (multi-sensorial referential, or tolerance level (according to Fox, 1975), or even "thymostat"), since each referential is probably a "mental object" identified by an activated assembly of neurons, according to Changeux, 1983).

    This referential determines the stimulation level at which the individual must begin to adjust by activating the appropriate emotion (fear, wariness, etc.) and adopting the most appropriate adaptive behavior (investigation, avoidance, flight, aggression, inhibition, etc.).

    The referentials that come into play are level of noise, visual agitation, intensity of olfactory stimulation, number of vibrations, occupation of three-dimensional space, flexibility or rigidity of movements, etc. Here we can directly see the overall differences between a city and rural environment of development.

    The corollary to the development of a puppy's attachment to its surroundings is its detachment from its parent(s).


    A puppy's malleability enables it to rapidly adapt to almost all human environments without undo stress.

    Risk factors

    Differences in the quality and amount of stimuli a puppy receives in its environment of development as compared to its adult surroundings determine the degree of risk it may not be able to adapt its sensorial referential (thymostat) and thus achieve emotional homeostasis (this includes development of phobias and anxieties). Clinical observation has also confirmed that it is easier to transfer from an environment with a high level of stimulation (city) to an environment with a low level (rural) than the contrary. A puppy raised in a deprived environment may be tempted to compensate for this lack of sensorial stimulation by self-stimulation: this is how certain stereotyped behavior develops, as well as self-centered behavior (Fox, 1975), such as self-induced dermatoses.

    Lastly, stimulus-poor puppies run the risk of developing hyper-attachments to their biological or adoptive parents (transposition of hyper-attachment to its new human masters), which is a source of intolerance to isolation, attention-seeking behavior, reutilization of behavior acquired during illnesses, etc.

    The Precocious Learning-Conditioning Phase

    This is another variant of the phase sensitive to emotional development that occurs between 3 � � and 12 � 2 weeks. Three behavioral situations are of particular interest in precocious learning: elimination, eating, and vocalization.


    Elimination is a reflex present at birth (it is provoked when the mother licks the puppy's perineum) and becomes spontaneous around 2-3 weeks. From 3 weeks on, the elimination reflex disappears and the puppy tends to leave its bedding to eliminate. At 8� weeks it defecates in specific spots, usually at a distance from its eating and sleeping area.

    Elimination behavior (1) is preceded by sniffing around, probably in search of typical odors (urine, feces, chlorine, ammonia, etc.) that will spark the elimination reflex, (2) occurs almost every waking hour, (3) is not activated for several hours during sleep.

    It is thus the dog breeder who conditions the location and medium favored for elimination. The acquirer (when he receives the 7-9 week old puppy) must then respect these socio-ecological conditions - he must limit the space available when the puppy is not under human control and provide the adequate elimination medium (why not a large litter box in an apartment?) placed at the right location (at least 2-3 meters from where the puppy eats and sleeps).

    Risk factors

    Clinical observation shows that when some puppies are limited to one spot and medium until the age of 15 weeks (puppies kept in the house and elimination on newspapers, for example) it becomes almost impossible for them to learn to use other media and locations (conditioning) and they retain themselves for hours when walking outside until they can eliminate on their preferred medium and spot.


    This ease of conditioning can be put to an advantage in teaching dogs to eliminate in gutters and other sewer outlets.


    Food conditioning studies have been conducted on cats that became vegetarian or imitated their mother who ate bananas. This type of conditioning is also well-known in humans: preferences or aversions for certain odors or tastes are already determined before birth (preference-aversion experiments with a rubber teat dipped in garlic sauce) (Cyrulnik, 1989). We can postulate an intra-uterine and post-natal food acculturation. To my knowledge, no experiments have been made to determine the duration of the food imprinting phase. It is possible that this phase is similar to the self-regulation phase, both in its duration and characteristics, since it engenders a food or feeding preference that is persistent but changeable over time.

    Risk factors

    Feeding a puppy solely on standardized food, invariable in taste and appearance (dry or moist) can lead to long-term preferences and rejection of other types of food (this has been clinically proven in cats). This problem can be avoided by giving the puppy a variety of food.


    Barking from distress when left alone in an unknown place increases from 3 to 6-8 weeks (maximum) then decreases until 12 weeks. The rising curve reflects a progressive attachment to a familiar place (attachment location) while the descending curve after 7-8 weeks is a sign of emotional maturing (more than habituation) and motivation to explore the unknown.

    When a puppy is acquired at 7 weeks and left alone at night it will bark in distress. This barking disappears spontaneously after a few days as it becomes familiar with its new home (with reassuring significance), unless its behavior receives positive reinforcement from its new masters (who come to pet, calm or scold the distressed puppy, or take it into their room, all signs of attention - thus positive reinforcement).

    The intensity and frequency of this vocalization normally diminish, to be replaced by intraspecific communication such as postures and rituals. Vocalization is used to ward off strangers ('territorial' defense) from the age of 11-15 weeks (see below). Some breeds have a greater tendency to bark than others (Hounds, Poodles, Yorkshires, etc.). Barking is easy to condition.

    Risk factors

    Interspecific communication with humans, also a vocal and verbal animal, reinforces the vocal element (learning by imitation), which then becomes preponderant, even disruptive.

    Play-fighting and learning to control biting

    Play-fighting, which begins at 3 weeks, can sometimes be painful when a puppy begins cutting teeth, especially when its ears are bitten. A bitten puppy whimpers or squeals. In a one-on-one or one-on-two fight the bitten puppy is able to turn the tide of the 'battle' and bite its adversary(ies). And this is precisely one of the "rules of the game": to change roles, with the biter becoming the bitten and vice versa.

    w The puppy learns to make an empathetic link between the opponent's squeal and the pain invoked.

    w Reciprocal biting negatively reinforces its intensity.

    w Biting is thus stopped, inhibited and controlled.

    These play-fights also lead to a certain hierarchization of relations (less than 25% among litter-mates at 5 weeks of age)

    The intensity of the bite is (congenitally) variable depending on the individual, line and breed, and can be modified considerably by training.

    From 7 weeks on puppies of a litter occasionally form groups to gang up on a lone puppy. In these cases biting is uncontrolled and the attacked puppy can be wounded (sometimes fatally). This phenomenon is more prominent in certain breeds or lines (Fox terriers, according to Scott and Fuller, 1965; Schnauzers, Huskies, and Malamutes among others, in my experience).

    From 11 to 15 weeks play-fighting recedes; it becomes less aggressive and more controlled. The fights become ritualized, a sign that stable hierarchical relations are being established. Agonistic co-operation is directed towards outsiders who are investigated and attacked in a manner more "serious" than play-fighting.

    Learning to control the intensity of its bite is actually part of a puppy's growing general control of its movements, enabling it to adopt postures and facial mimics which become the prevalent form of communication in animals having highly developed brains.

    Risk factors

    If the puppy's owners fail to reproduce play-fighting postures and allow it to bite their hands, arms and legs, this can lead to:

    1. the puppy's hierarchical dominance that can induce relational problems later on (competitive aggressivity, sociopathy).

    2. failure to control the intensity of biting and risk of serious (wounding) biting in minor confrontations.

    3. Human skin is more fragile than a dogs. Dogs that are family pets must be given more thorough training in controlling the intensity of their bite.

    4. A dog encouraged to pull at objects it holds in its jaws reinforces the biting reaction, which is undesirable in a family pet (although it may be useful for police and guard dogs).

    5. And lastly, failure to develop a dog's general motor control encourages hyperkinetic forms of behavior.

    Weaning-Detachment and (Food) Hierarchization

    A mother's care and attachment towards her puppies are strongest during the first 3 weeks of life, and after that progressively recede.

    The first phase of weaning begins around 5 � � weeks; the mother growls and bares her teeth when puppies attempt to nurse (painful when the puppies cut their teeth); the puppy yaps and rolls over on its back and then learns to keep away from its mother's teats (Scott and Fuller, 1965). An aggression-inhibition relationship - a dominant-submissive hierarchization - is then established between the mother and puppy for access to the mother's teats.

    This attitude is extended towards other mother-young conflicts and adopted in the presence of other adults, as shown by the following personal observation. In a husky breeding station the presence of the mother beyond the 5th week led to her puppies' spontaneous submission to the adults of the pack. In another station the mother was taken from the breeding kennel when her puppies were 5 weeks old; these puppies were not submissive to adults when they were first placed with the rest of the group at 12 to 16 weeks. They did not use the submissive posture (rolling over); the ritual was not acquired.

    The presence of the mother is thus favorable, even necessary, for the development of appeasement-submission rituals and for the puppy's hierarchization in the adult pack.

    Lactation wanes around 7 to 10 weeks.

    From the age of 5 weeks the puppies begin to growl to gain possession of their food. At the mother's arrival the puppies assemble in the attempt to nurse and wait for their mother to regurgitate pre-digested food: they wag their tails, lick and bite at the mother's chops and try to take regurgitated food directly from her mouth.

    The mother does not compete with her young (7 weeks of age) and allows them full access to the food (even if it is a bone) (Scott and Fuller, 1965). This free access ends as the puppy becomes autonomous and takes its place in the adult hierarchy (Pageat). At about 16 weeks the puppies must take their place in line for food, i.e. after the dominant and sub-dominant members, almost last. The puppies share and fight over what is left, and gobble it up rapidly, to the complete indifference of the dominant members who return to other activities. Puppies attempting to snitch food while the dominant members are eating are snapped at, growled at and threatened with being bitten. Some puppies nonetheless manage through appeasement rituals to grab some food and escape with it to a corner. Hierarchization for food privileges thus occurs around 16 weeks.

    When a pair of puppies not competing for maternal attention are given a bone there is aggressive competition ending with a winner and a looser. The fight is rarely traumatic since adult fighting capacities are as yet undeveloped. Hierarchization between litter-mates varies with age and breed (Scott and Fuller, 1965):

    • 25% at 5 weeks,

    • 50% at 11 weeks,

    • 75% at 15 weeks in terriers,

    • 75% at 1 year in basenjis and shelties,

    • 50% maximum in cockers and beagles.

    Food hierarchization varies by race and age. According to Scott and Fuller (1965), it is predominant in short-haired fox terriers and basenjis (the male dominates the female); and rare in shelties at 11 and even 15 weeks (less than 50% of couples although this figure increases to 75% around 1 year). This breed has been shown to "respect" (accept) the female's priority to food. Food hierarchization is average in cockers and beagles with no predominance of either sex. The sheltie, on the other hand, develops a strong hierarchy in defending the nest (spatial-territorial) and submissive members (females) are pushed inside the nest.

    The more "aggressive" the litter (line, breed), the greater the tendency for linear hierarchization.

    All puppies that are correctly socialized will "leap" towards humans who enter their area (bed, cage,...). The boldest ones are generally the most dominant; they push back their submissive pack-mates, barring access. Choosing a bold puppy (to avoid adopting a seemingly unsociable one who stays at the back of the cage) may thus mean selecting a dog that will be more aggressive to other dogs.

    In conclusion: this period leads to food hierarchization among litter-mates from 5 to 15 weeks (occasionally later), between puppies and adults from 4 � � months, and reutilization of submissive postures (dorsal-lateral decubitus) towards adults (from 5 weeks) and appeasement postures (nibbling the chop and extending the paw) from 8 weeks.

    Risk factors

    There can be several risks involved in acquiring a puppy as a pet:

    1. The human desire to give and receive attention is opposed to the normal (agonistic) parental behavior to wean the puppy, detach oneself and encourage autonomy. The result can be attachment, even hyper-attachment, later engendering a separation anxiety syndrome.

    2. The human tends to fear for the puppy's health and thus pays particular attention to its appetite, watching it while it eats, indulging it when it begs, worrying about finicky appetites or loss of appetite, varying food, and hand-feeding, which become invested with the social symbol of dominance.

    3. The anthropomorphic tendency of a human-dog relationship to develop into that of parent-child, or parent-baby postpones the puppy's training towards adulthood at 5-10 months as well as the order-obedience relationship that is part of hierarchization. This delay can foster sociopathy and certainly does not facilitate obedience.

    4. Furthermore the lack of rituals lead to their malfunction, and even changes in their significance: if a dog in a submissive posture is petted (positive reinforcement) it will adopt this posture more often in the search for attention. The master then obeys by petting it. The relationship risks reverting to one with a demanding-dominant dog and a obedient-submissive owner.

    5. Dogs have a cynomorphic approach to the human-dog relationship, seeing it first as one between puppy-adult dog, then as an interaction between pack-mates (pre-adult-adult). A dog views human behavior through the social lens of its own species and attempts to gain privileges as high as possible on the hierarchical scale.

      These risks are avoided when dog owners behave in a way that can be assimilated to the parent-dog relationship. It is clear how the Western world's custom of acquiring pets favors the emergence of hyper-attachment and sociopathies (dog as a toy, an object (a live teddy bear), a substitute for children, a catalyser for social reactions, spoiled dog, etc.).

    The Cognitive Sensitisation-Rationalisation Phase in Pre-Puberty

    In clinical practice we have observed cases where phobic behavior (both towards the dog's immediate surroundings and towards humans with which the dog has little contact) and anxiety develop in pre-puberty. This occasionally leads to an anxiety syndrome which I call "anticipated defense behavior" (Dehasse, 1990a). A Bernese sheep-dog (raised in Belgium) developed intermittent anxiety (with pathological anticipations) around the age of 6 months, despite a social and sensorial enrichment between 3 weeks and 4 months. Her sister acquired the same tendency in a completely different environment (Netherlands), as did her brother (in Switzerland). A family of briards (Brie sheep-dogs) displayed the same tendency, despite differences in the surroundings in which they were raised. This enables us to propose two hypotheses: the hypothesis of inherited temperament and that of the phase of pre-puberty sensitization.

    A bibliographic study confirms there is a phylogenetic and/or epigenetic tendency for pre-puberty sensitization. Fox (1978) studied primary and secondary socialization in wild dogs and other canines that were raised in identical environments and had daily contact with the trainer and intermittent contact with unfamiliar humans. The wild canines all remained attached to the trainer, at least until they reached maturity, and then became less tolerant to contact with or proximity to the trainer all the while welcoming him with appeasement postures (whereas in the beginning he was welcomed with active postures: jumping, licking, nudging).

    Wariness of strangers develops:

    • quickly in the solitary species (from 4 months in foxes),

    • later in species of average sociability (around 1 year for jackals and coyotes),

    • and much later in social species such as wolves (between 6 and 18 months) or dogs (beagle, pointer or Chihuahua - between 1 and 2 years).

    There is a correlation in canines between wariness and the arrival of puberty (10 months in the coyote, 2 years in the wolf), except in foxes (wariness largely precedes puberty) and dogs (wariness follows puberty which appears around 6 months). In dogs, precocious neutering can delay or preclude the emergence of wariness towards strangers (Brunner, 1968, in Fox, 1978), which could possibly confirm the tendency's hormonal cause. It is Fox's opinion that domestication led to a dissociation between gonadal maturing (precocity) and maturing of the central nervous system (late).

    Figures given for dogs, however, are hardly conclusive. We all know how the age of puberty, temperament, emotivity, sociability etc. can vary among breeds and individuals. It is thus normal to see the appearance of wariness towards strangers (or the unknown) or a loss of certain social experience and sensorial references between 4 months (as in foxes) and 2 years (as in wolves). This can also be compared to the development of so-called territorial aggressivity.

    Woolpy (1968, in Fox, 1975) accustomed adult wild wolves to contact with humans in 6 months' time; he then isolated them somewhat from humans: in this case they retained their socialization experience. He also accustomed wolf cubs to humans, then isolated them: in this case there was de-socialization (instability of precocious socialization). Young animals need continuous reinforcement.

    The same holds for dogs: when a normally socialized puppy is isolated from humans and placed in a kennel from 3-4 months of age to 6-8 months he becomes fearful in the presence of humans, even the trainer. Woolpy's interpretation (for wolves) is that socialization is limited by fear of the unknown. Although the behavioral signs are precocious, the subjective element evolves gradually over a year (at least). Thus before socialization can be acquired, the subjective (cognitive) element of fear must first mature.

    In other words, fear of the unknown has both an emotional and behavioral phase (starting around 5 weeks) and a cognitive phase (near puberty).

    It is my hypothesis that an optimal period of attraction-habituation (acquiring sensorial and emotion homeostasic referentials) closes with an emotional and behavioral phase of aversion-fear of the unknown (5-14 weeks). There follows a vulnerable period of cognitive sensitization at pre-puberty or puberty during which minor trauma can occasionally entrench wariness or fear, (ill�)adaptations, and cognitive and emotional distortions that are undesirable in a dog living among humans in a city environment.

    Risk factors

    Sensitization (and the often indissociable generalization) is the process that engenders wariness, fear, phobia and anxiety. The cognitive process it entails leads to a dog's anticipating harmful situations that exist only in its mind (in a way, fear of being attacked) and thus behavioral strategies (defense mechanisms: flight, aggression, inhibition).

    It is at this sensitive age that dogs often begin group training courses. It is imperative for the training environment to be controlled to ensure the dog does not suffer any psychological trauma. At pre-puberty, however, dogs emit pheromones that activate demonstrations of authority by the group's dominant dogs. It is best to begin group courses around 3 months of age, so that the dogs can become familiar with each other and hierarchies before puberty.

    Puberty and Hierarchization

    Dogs are social animals that need company, living in a hierarchical pack (or family-pack). In clinical practice we continually observe cases of conflicts (competitive aggression) at puberty, and later in adulthood. These conflicts revolve around access to the opposite sex (intra- or interspecific), but they can also arise over occupation of certain areas of the group's common space (in the house in cases of conflicts with the dog's owners, and rarely outdoors), in particular feeding and sleeping areas.

    Our hypothesis is the following: an optimal period of intraspecific socialization (identification) is followed by several crucial periods of hierarchization that occur in successive phases: food, territory, socio-sexual at puberty and maturity.

    Pageat (1984) demonstrated the existence of a triple surge of social aggressivity in dogs (male spaniels):

    1. the first peaks around 4-5 months with the dog returning to normal around 6-6� months, when it begins obedience lessons (the owners assert their dominance);
    2. the second surge coincides with the production of sexual steroids (�5 months);
    3. the third corresponds to a "second attempt to obtain reproduction rights" and only occurs in dogs who are allowed to live in the house. Pageat explains this as follows: in a dog-pack, adolescent males at puberty are pushed to the fringe of the group (by the alpha male and the other older males). The third aggressivity surge does not appear at this time. This is because in a group, the dominant members react and put the young dog in its place each time it tries to compete aggressively, barring its access (satellisation) to socially invested areas and sexual partners. If the dominant members fail to react, aggressivity is reinforced and the young dog rises in hierarchy.

    In Fox's experiment (1975) with various wild and domesticated canines, there was a surge in aggressivity in male jackals and wolves at the onset of puberty which increased until it peaked at 2 years. Aggressivity was directed toward males (canines and humans). Note that canines are perfectly capable of distinguishing the sex of humans, even when they are dressed alike; this is probably through their sense of smell. Fox also pointed out that competitive aggressivity may not appear in wolves (males as well as females) until 4-5 years of age (maturity).

    We have seen that hierarchization occurs during a first "food" phase between puppies (from 5 weeks and is practically established, depending on the breed, between 3 to 12 months), then between adults and puppies (around 4 � � months). This phase corresponds to the first surge of social aggressivity identified by Pageat.

    The second phase of hierarchization, puberty, is sexual, social and zonal-spatial. The young dog develops an interest for the opposite sex and for areas occupied by the dominant members, who react by pushing the adolescent to the fringe of the group. The process is complex: sexual pheromones are awakened at puberty, activating "desire" (Vincent, 1986), the dog exhibits courting behavior and is rejected outright by the dominant member of the same sex, the only one of the group with the right to exhibit his/her sexuality openly. The adolescent is pushed from areas occupied by the dominant members (high-placed positions, controlling passages, preferential sleeping areas, etc.). It no longer has the right to greetings, licking and other social attentions given by the other dogs. This is why this phase is social, spatial and sexual.

    This phase is generally accompanied by territorial defense behavior. In some breeds it occurs earlier, appearing from 2 months. In females, progesterone favors territorial defense behavior, just as it favors whelping and pseudocyesis.

    A third phase of hierarchization occurs at maturity (adulthood), an age that varies in dogs depending on the breed (from 8 months to 3 years). It reproduces the same characteristics as the second phase, only this time with all the weapons, strength and passions of a mature adult.

    Risk factors

    If adolescent dogs do not undergo hierarchization-satellisation, they gain hierarchy - access to the privileges of the dominant member. The dog's relation with its master thus becomes ambivalent, with conflicting messages: demands (dominance) - tolerance (submission). The lack of comprehensible appeasement rituals favors attitudes of competitive aggression (sociopathy) or substituting behavior (sometimes self-directed).

    Discussion and Conclusions

    No quantitative studies have been made on intra-breed variability, and inter-breed studies have only concerned a few family lines in selected breeds. It is thus impossible to form conclusions based on breed in view of the number of dog breeds identified up to now (more than 200).

    Furthermore, the studies we have cited have never been conducted on a large number of animals. The results mentioned are thus qualitative and speculative, as are the dates and periods.

    Nevertheless, a dog's ethogenesis evolves in (at least) three overlapping phases, each related to a particular system: the neuro-vegetative (neuro-glandular) - 1 to 7 weeks, the emotional (limbic) system - 3 � � to 12 � 5 weeks, and the cognitive system (cortex) - 5 � 1 to 18 � 10 months).

    The different phases of development


    from -4 (before birth) to +7 weeks


    from 3�� to 12�5 weeks

    Filial, fraternal and sexual imprinting

    Intraspecific sociability


    from 3�� to 12�2 weeks

    Socialization - Thymostasis - Conditioning, etc.


    5�1 to 18�10 months

    Hierarchization - Rationalization - Territorialisation

    Each phase presents a series of risks that can undermine the dog-dog and dog-human relationship. A dog's epigenesis engenders multiple temperaments that can be partially foreseen by controlling its environmental stimuli. One factor favorable to emotional and relational well-balance of a dog that must live with humans in a city context is enrichment in the breeding environment.

    • It is the breeder's role is to ensure temperamental selection and to enrich the development environment (under veterinary guidance).

    • The role of the veterinarian is essential because he/she sees the animal from 6 to 16 weeks for its vaccinations. He/she thus theoretically has several occasions to assess the puppies' early emotional and behavioral development and can recommend preventive measures and training techniques.

    • The media can also play a role in educating potential dog owners to adapt their relational needs to the dog's ecological and social reality, rather than their own personal wishes.

    • The trainer must not only inculcate the bases for instrumental learning, he/she must also take advantage of having a group of dogs to continue their socialization and avoid de-socialization, both towards other dogs and towards humans.

    • Dog owners must find adequate counseling to prevent multiple relational (systemic) and behavioral dysfunctions in their dogs. But they must first be aware of the problem and know where to go for advice. It is up to the veterinarian to inform them!

  • The 7 Stages of Puppy Development

    In order to understand why your puppy doesn�t listen to you at times, you need to understand each stage of development a puppy goes through as it matures.

    Let�s take a look at the different stages, but before we do, keep in mind that these stages are generalizations � each dog will progress at its own pace.

    Stage 1: The Transitional Stage | 2-3 Weeks

    The Transitional stage generally lasts from age two to three weeks, and it�s during this time that your puppy�s eyes will open, and he�ll slowly start to respond to light and movement and sounds around him. He�ll become a little more mobile during this period, trying to get his feet underneath him and crawling around in the box (or wherever home is.) He�ll start to recognize mom and his littermates, and any objects you might place in the box.

    Stage 2: The Almost Ready To Meet The World Stage | 3-4 Weeks

    The Almost ready to meet the world stage lasts from 3 to about 4 weeks, and your puppy undergoes rapid sensory development during this time. Fully alert to his environment, he�ll begin to recognize you and other family members. It�s best to avoid loud noises or sudden changes during this period � negative events can have a serious impact on his personality and development right now. Puppies learn how to be a dog during this time, so it�s essential that they stay with mom and littermates.

    Stage 3: The Overlap Stage | 4-7 Weeks

    From 3-4 weeks your puppy begins the most critical social development period of his life � he learns social interaction with his littermates, learns how to play and learns bite inhibition.

    He�ll also learn discipline at this point � Mom will begin weaning the pups around this time, and will start teaching them basic manners, including accepting her as the leader of the pack. You can begin to introduce food to the pups starting around the 4th week � transition gradually as Mom weans them.
    Continue handling the pups daily, but don�t separate them from either Mom or litter mates for more than about 10 minutes per day. Puppies that are removed from the nest too early frequently are nervous, more prone to barking and biting and have a more difficult time with socialization and training. Puppies need to be left with Mom and siblings until at least 7 weeks of age - and preferably a little longer - for optimum social development.

    Experts say that the best time in a puppy�s life to learn social skills is between 3 and 16 weeks of age � that�s the window of opportunity you have to make sure your puppy grows up to be a well-adjusted dog. It�s extremely important to leave your puppy with Mom and his littermates during as much of this period as possible. Don�t discipline for play fighting, housebreaking mistakes or mouthing � that�s all normal behavior for a puppy at this stage.

    Stage 4: The �I�m Afraid of Everything� Stage | 8 Weeks to 3 Months

    The �I�m Afraid of Everything� Stage lasts from about 8 weeks to 3 months, and is characterized by rapid learning as well as a �fearful period� that usually pops up at around 8 to 10 weeks. Not all dogs experience this, but most do, and they�ll appear terrified over things that they took in stride before. This is not a good time to engage in harsh discipline (not that you ever should anyway!), loud voices or traumatic events.

    At this time your puppy�s bladder and bowels are starting to come under much better control, and he�s capable of sleeping through the night. (At last, you can get some rest!) You can begin teaching simple commands like: come, sit, stay, down, etc. Leash training can begin. It�s important not to isolate your puppy from human contact at this time, as he�ll continue to learn behaviors and manners that will affect him in later years.

    Stage 5: The Juvenile Stage | 3 Months to 4 Months

    The Juvenile stage typically lasts from 3 to 4 months of age, and it�s during this time your puppy is most like a toddler. He�ll be a little more independent - he might start ignoring the commands he�s only recently learned � just like a child does when they�re trying to exert their new-found independence. As in �I don�t have to listen to you!� Firm and gentle reinforcement of commands and training is what�s required here.He might start biting you � play biting or even a real attempt to challenge your authority. A sharp �No!� or �No bite!� command, followed by several minutes of ignoring him, should take care of this problem.

    Continue to play with him and handle him on a daily basis, but don�t play games like tug of war or wrestling with him. He may perceive tug of war as a game of dominance � especially if he wins. And wrestling is another game that can rapidly get out of hand. As your puppy�s strength grows, he�s going to want to play-fight to see who�s stronger � even if you win, the message your puppy receives is that it�s ok to fight with you. And that�s not ok!

    Stage 6: The Brat Stage | 4-6 Months

    The Brat Stage starts at about 4 months and runs until about 6 months, and it�s during this time your puppy will demonstrate even more independence and willfulness. You may see a decline in his urge to please you � expect to see more �testing the limits� type of behaviors. He�ll be going through a teething cycle during this time, and will also be looking for things to chew on to relieve the pain and pressure. Frozen doggie bones can help sooth him during this period.

    He may try to assert his new �dominance� over other family members, especially children. Continue his training in obedience and basic commands, but make sure to never let him off his leash during this time unless you�re in a confined area. Many times pups at this age will ignore commands to return or come to their owners, which can be a dangerous, even fatal, breakdown in your dog�s response to you. If you turn him loose in a public place, and he bolts, the chances of injury or even death can result � so don�t take the chance.

    He�ll now begin to go through the hormonal changes brought about by his growing sexual maturity, and you may see signs of rebelliousness. (Think adolescent teen-age boy!) If you haven�t already, you should have him neutered during this time. (Or spayed if you have a female.)

    Stage 7: The Young Adult Stage | 6-18 Months

    The Young Adulthood stage lasts from 6 months to about 18 months, and is usually a great time in your dog�s life - he�s young, he�s exuberant, he�s full of beans � and yet he�s learning all the things he needs to become a full-fledged adult dog.

    Be realistic in your expectations of your dog at this time � just because he�s approaching his full growth and may look like an adult, he�s not as seasoned and experienced as you might expect. Gradually increase the scope of activities for your dog, as well as the training. You can start more advanced training during this period, such as herding or agility training, if that�s something both of you are interested in. Otherwise, extend his activities to include more people and other animals � allow him to interact with non-threatening or non-aggressive dogs.

    Congratulations! You�ve raised your puppy through the 7 stages of childhood, ER, I mean puppyhood, and now you have a grown-up, adult dog! Almost feels like you�ve raised a kid, doesn�t it?

What happens when - how your puppy changes and develops

"Puppies provided with poor socialization or deprived of environmental exposure often develop lifelong deficits and dysfunctional behaviors. A puppy isolated early in life from other puppies and humans will not only fail to establish satisfying social contact with conspecifics or enjoy companionship with people later in life (such puppies are extremely fearful of any social contact), they will also exhibit widespread behavioral and cognitive disabilities as well. Isolated puppies exhibit poor learning and problem-solving abilities and are extremely hyperactive or rigidly inhibited, are emotionally over-reactive and unable to encounter novel social or environmental situations without extreme fear and avoidance, and are socially and sexually incapacitated." - Handbook of Applied Behavior and Training, Steven R. Lindsay

Developmental stages


Learning and Development

What you should be doing

Early development & reflexive behavior:

Neonatal period

Birth to 12 days

Puppy can't hear or see well, stays close to mother and littermates.


Breeder provides warm environment. Dr. Michael Fox conducted a study showing mildly stressing puppies during the first five weeks develops dogs which are superior when put in learning or competitive situations. They are better able to handle stress, are more outgoing and learn more quickly. Mild physical stress at an early age will actually increase the size of the brain.

Transitional period


13 to 20 days

Eyes open, puppy can hear, begins to walk in a wobbly fashion.They will begin to hear and will respond to taste and smell.

This is the time to introduce novel stimuli to the whelping box such as a plastic milk bottle, knotted towel, cardboard box, etc. This is also a time to introduce puppies to friendly cats. It is important to continue picking up the pups daily, admire them, talk to them, and spend a few minutes with each one individually.

Primary Socialization begins.

Awareness period

21 to 23 days

Puppy is able to use senses of sight and hearing.

Learning begins.

It is a time of very rapid sensory development. A stable environment is crucial. It is important not to overload them. Radical changes in the environment must be avoided, i.e. do not move the whelping box!

It is essential that the puppy remain with the litter and the mother.

Each day introduce a new surface such as concrete, linoleum, wood, carpet, matting, etc. Taking them two at a time will make it less stressful than one at a time. Very mild auditory stimuli is introduced, such as a radio playing quietly.

Learning he's a dog:

Canine Socialization

Primary Socialization period - 3 to 5 weeks

Secondary Socialization period - 6 to 12 weeks

"This period is especially important for the development of a stable emotional temperament and affective tone. Many social and emotional deficits observed in adult dogs are believed to result from removing puppies too early from the mother and littermates." - Steven R. Lindsay

21 to 49 days

Puppy learns species specific behavior that makes him a dog (biting, chasing, barking, fighting and body posturing.

Learns to accept discipline from mother and to use submissive postures.

Learns not to bite too hard.

Learns to relate to other litter mates and develops a pack hierarchy through play.

Mother begins to wean puppies between 4-8 weeks, but should be allowed as much time with the pups as she wants.

Puppies require plenty of playtime with littermates, so they can socialize.

Leaving the litter before 7 weeks can affect the puppy's ability to get along with other dogs later and they will likely have trouble learning to inhibit the force of their bite.

Put an open crate in the puppy pen. Clear distinction between sleep and play area should be made. This ensures the puppy can leave his sleeping area to eliminate. This will make housetraining later much easier.

Each puppy should have one-on-one individual attention with humans. Take two at a time for short car rides.

Occasionally isolate puppies to prepare them for separation.

Puppy's rate of mental development will now depend on the complexity of their environment. Exposure to a variety of noises and different floor surfaces is important.

Begin positive training sessions at 5 weeks.

Into a new home with a human family.

Human Socialization

"100 new people by 12 weeks" - Dr. Ian Dunbar, PhD

�From now to the 16th week of the puppy�s life, his basic character is set by what he is taught. This will apply especially to his attitudes toward people and toward his ability to serve them the very best he can." -Pfaffenberger

7 to 12 weeks

The 49th day. The brain waves of the puppy are the same as a mature dog, but the puppy is a clean slate.

Puppy should be completely weaned from mother.

This is the age when most rapid learning occurs. Greatest impact on future social behavior will be made by any experience that happens at this point.

The window of opportunity is closing. Although puppies can continue to learn to be comfortable with new things, it is not as easy.

Best time to bring a puppy into its new home is around week 7or 8. "The 49th day" is recommended by Guide Dog raisers and supported by studies.

Absolutely critical period in which puppy should be socialized - maximize this time! Enroll in a good puppy class!

Ideal time to capitalize on educating your puppy.

Take into account puppy's physical limitations and short attention span.

Fear Imprint Period

Experiences a puppy perceives as traumatic during this time are generalized and may affect him all his life. It is a fact that a dog is most likely to develop an avoidance response if subjected to physical or psychological trauma during these four weeks.

8 to 11 weeks

This period falls within the human imprint period.

Anything that frightens the puppy during this period will have a more lasting effect than if it occurred at any other time.

Keep training fun. Use short sessions, and keep all training positive. Gentle guidance and management are essential. Set your puppy up to succeed. This kind of mindset will enable you to be successful, as you continue to socialize your puppy.

Puppies should not be shipped during this period, elective surgery should be put off until the 12th week, and necessary visits to the vet should be made fun.

Learning to compete and cope.

Seniority Classification

Social dominance - 10 to 16 weeks

10 to 16 weeks

Puppy has been in the home for approximately six weeks. This period is known as the "period of cutting teeth and apron strings." Pups will attempt to clarify and resolve question of leadership.

So long as you provide structure, control and leadership, this transition should be relatively painless.

If these things have not been provided, all heck is about to break loose!

Flight Instinct Period

"Seems to forget everything previously learned."
- "How to Raise a Puppy You Can Live With"

Even if you have done your homework it does not mean your puppy won't go through this - just be aware of it and ride it out.

Just keep your pup on a leash until this passes.

4 to 8 months

This stage can last from a few days to several weeks and can occur anytime during this period.

A puppy will test its wings.

He may challenge you in an attempt to resolve the question of leadership.

He may not come when called.

He may not play fetch even though he once did.

He will be uncomfortable because his adult teeth are growing in.

It is because of this stage that prevention over cure is advocated -- you must start socializing and training before now! When you notice a change in your dog during this time, he is probably going through his "flight instinct" period. Like a teenager going through puberty, your puppy is changing physiologically. Your awareness of these changes in behavior will help get you through this commonly difficult period.

This is the time when obedience schools get most of their calls. Puppies that have not been socialized and worked with take a different path in life than pups that have.

Be prepared with appropriate chew bones (large enough so that the pup will not choke) to help with your pup's need to chew. Use a long line in the park if your pup is not coming when called.

Second Fear Period

Many dogs will show a rise in their level of aggression (reactivity) during this time. They may become protective and territorial, and may make a new attempt to dominate owners. Incidents of teenage flakiness may recur.

6 to 14 months

In large breeds this period could extend longer since it is tied to sexual maturity. Incidents may occur more than once.

Corresponds with growth spurts. Therefore it may happen more than once as the puppy matures.

May suddenly be apprehensive about new things or shy or timid of new people or situations. Most of height growing is over, but pup will start to fill out over the coming year.

Puppy begins to mature sexually: male begins to lift leg, and female has first heat period anywhere from 6-12 months. Puppy coat being replaced by adult coat, starting down the spine.

This is a fear of new situations and are handled with the utmost patience. The dog is encouraged to work it out on his own. If anything, it is better to ignore the whole situation than to reinforce the fear by praising the dog or petting him while he is afraid. When you "reassure" a dog with pets and "it's okay, fella", you are telling him it is okay to be frightened and you are creating a potential problem.

If your puppy appears apprehensive, avoid confrontation.

Build confidence through training.

Avoid any potentially overwhelming circumstances you cannot personally oversee, such as shipping your pup in the cargo bay of an airplane.


Are you done socializing? NO! Like your training efforts, which continue on into adulthood and throughout your dog�s entire life, you are never done with socialization. He still needs to meet and greet people, go places with you, and continue to share your world and your experiences, if you want him to continue to be the happy, friendly dog he is today.

1-4 years

Refers to sexual maturity as opposed to being full-grown. Smaller dogs mature earlier, larger dogs later. If you were lax in your work earlier on, you may now see the things you have missed: object guarding, unfavorable reactions towards unfamiliar people, animals, or things that your dog missed during the socialization stage.

Until this period has been reached, it is recommended that your pup remains crated or the equivilent (structure) when you are not available to supervise his behavior.

You will know when your dog can be trusted by testing him for short periods (10-15 minutes) while you leave the house. If your dog is damaging property while loose, he is not ready.

Information gleaned from:
"The Handbook of Applied Dog Behavior and Training", Steven R. Lindsay
Weimaraner Club of America website, article by Ellen Dodge
"The Urban Puppy Toolkit"
"How to Raise a Puppy You Can Live With." Clarice Rutherford & David H. Neil
"The New Knowledge of Dog Behavior" Clarence Pfaffenberger
Instructor Training Course - Dr. Ian Dunbar, PhD

Developmental Stages Of Puppy Behavior

Dog Behavior and Training >> Developmental Stages Of Puppy Behavior

Although feeding time is important, it's also vital to include petting, talking and playing, in order to help your puppy build good "people-skills." Well-socialized mothers are more likely to have well-socialized puppies. Puppies "feed" off of their mothers' calm or fearful attitude toward people. Puppies are usually weaned at six or seven weeks, but are still learning important skills as their mother gradually leaves them more and more. Ideally, puppies should stay with their littermates (or other role-model dogs) for at least 12 weeks.

Puppies separated from their littermates too early often don't develop appropriate "social skills," such as learning how to send and receive signals, what an "inhibited bite" means, how far to go in play wrestling and so forth. Play is important to help puppies increase their physical coordination, social skills and learning limits. Interacting with their mother and littermates helps them learn "how to be a dog" and is also a way to explore ranking ("who's in charge").

Skills not acquired during the first eight weeks may be lost forever. While these stages are important and fairly consistent, a dog's mind remains receptive to new experiences and lessons well beyond puppy-hood. Most dogs are still puppies, in mind and body, through the first two years.

The following chart provides general guidelines for the stages of development.

0 - 2 weeks = Neonatal

  • Most influenced by their mother.
  • Touch and taste present at birth.

2 - 4 weeks = Transitional

  • Most influenced by their mother and littermates.
  • Eyes open, teeth erupt, hearing and smell developing.
  • Beginning to stand, walk a little, wag, bark.
  • By four or five weeks, sight is well-developed.

3 - 12 weeks = Socialization

  • During this period, puppies need opportunities to meet other dogs and people.
  • By four to six weeks they're most influenced by their littermates and are learning about being a dog.
  • From four to 12 weeks they're most influenced by their littermates and people. They're also learning to play, including social skills, inhibited bite, social structure/ranking and physical coordination.
  • By three to five weeks they're becoming aware of their surroundings, companions (dogs and people) and relationships, including play.
  • By five to seven weeks they're developing curiosity and exploring new experiences. They need positive "people" experiences during this time.
  • By seven to nine weeks they're refining they're physical skills/coordination (including housetraining) and full use of senses.
  • By eight to ten weeks they experience real fear -- when puppies can be alarmed by normal objects and experiences and need positive training.
  • By nine to 12 weeks they're refining reactions, social skills (appropriate interactions) with littermates and are exploring the environment, spaces and objects. Beginning to focus on people. This is a good time to begin training.

3 - 6 months = Ranking

  • Most influenced by "littermates" (playmates now include those of other species).
  • Beginning to see and use ranking (dominant and submissive) within the pack, including humans.
  • Teething (and associated chewing).
  • At four months they experience another fear stage.

6 - 18 months = Adolescence

  • Most influenced by human and dog "pack" members.
  • At seven to nine months they go through a second chewing phase -- part of exploring territory.
  • Heightened exploration of dominance, including challenging humans.
  • If not spayed or neutered, beginnings of sexual behavior

Stages of puppy development

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Just as the saying "a chip off the old block" often holds true for humans, it can apply to dogs as well. Puppies that are well-socialized are more likely to come from dogs that are well-socialized.

A basic part of a pup's socialization is based on their mother's attitude--relaxed or skittish--toward people. The way you interact with your new puppy can play a big role, too. Playing, petting, and talking with your pup can help him or her develop the "people skills" needed to be a good member of the family and the neighborhood.

While weaning for puppies can take place at six to seven weeks, they are still learning important skills from their littermates as their mother gradually leaves them for longer periods of time. Puppies that stay with their litter for at least three months are more likely to develop good social skills as they act as role models for each other.

When puppies are separated from their littermates too early, they often fail to develop key social skills, such as sending and receiving signals, the hierarchy process (who is in charge), how far to go in play-wrestling, what mouthing pressure is acceptable (inhibited bite), and so forth. Play is important for puppies. It increases their dexterity, social interaction, and helps them to learn their boundaries.

Through these interactions with their mother and littermates, puppies learn what being a dog is all about. During the first eight weeks of age, skills not acquired may be lost forever.

Most dogs are considered puppies for up to two years of age, though puppyish behavior may end sooner or last longer in some breeds. The stages listed below are essential and fairly constant. However, dogs are open to new knowledge and training well beyond the puppy years. Here are some general guidelines for puppies' stages of development.

The neonatal stage: Birth to two weeks

  • The senses of touch and taste are immediately present after birth.
  • The mother has the most influence over the puppy.

The transitional stage: Two to four weeks

  • Mother and littermates continue to influence a puppy's behavior.
  • The sense of hearing and smell develop, eyes open and the teeth begin to appear.
  • A puppy begins to stand, walk a little, wag its tail, and bark.
  • A puppy's eyesight is well-developed by the fourth or fifth week.

The socialization stage: Three to twelve weeks

  • A puppy needs occasions to meet other pets and people during this stage.
  • By three to five weeks, play becomes important as a puppy becomes aware of his or her surroundings, companions (both people and dogs), and relationships.
  • The influence of the puppy's littermates increases at four to six weeks as he or she learns more about being a dog.
  • From four to twelve weeks, a puppy's interaction with people becomes more influential. With littermates, the puppy learns to play, develops social skills, learns the inhibited bite, explores his or her social boundaries and hierarchy, and improves physical coordination.
  • By five to seven weeks, a puppy needs positive human interaction as he or she develops curiosity and explores new experiences.
  • A puppy has full use of his or her senses by seven to nine weeks. A puppy is refining his or her coordination and physical ability, and can begin to be housetrained.
  • At eight to ten weeks, a puppy can experience real fear involving everyday objects and experiences. During this stage, a puppy needs support and positive reinforcement.
  • Enhancing responses, advancing social skills with littermates (proper contact), and investigating the surroundings and items takes place from nine to twelve weeks. This is a good time to begin elementary training as a puppy will begin to focus on people.

The ranking stage: Three to six months

  • Ranking (dominance and submission) within the household or "pack," including people, is seen and used by a puppy in this stage.
  • A puppy's play group, which may now include those of other species, becomes influential in his or her life.
  • Teething and chewing begins.
  • A puppy experiences another fear stage at four months of age, so be prepared with positive reinforcement and introductions to objects and situations.

The adolescence stage: Six to eighteen months

  • A puppy is most affected by human and dog "pack" members.
  • A puppy may challenge people as part of exploring his or her dominance in the "pack."
  • At seven to nine months, a puppy will begin exploring more of his or her territory, prompting a second chewing phase.
  • A puppy will experience the beginnings of sexual behavior if not spayed or neutered.

         Puppyhood and Beyond Puppies are growing animals. When they are young, they learn much and what is learned has a lasting impact. Even sexual patterns, which emerge as puppies mature, can be affected by early experience. All dogs, regardless of breed, pass through various stages as they grow and develop, physically, mentally, and psychologically. Psychologists use the term critical period to describe a specific time in a dog's life when certain experiences have a lasting effect upon their psychological development. Understanding these critical periods and a dog's stages of development will better help you to understand your dog's behavior and how to handle him during these special times. Additionally, puppies benefit greatly when their owners understand their development.

         Puppy Toddlers (3 - 6 Weeks) During the Toddler period, puppies emerge on their own from the litter. They venture into the surrounding environment. This emergence from the litter is a gradual and continual learning experience. During this stage of development puppies learn basic behavioral patterns specific to dogs. While playing, they practice different body postures, learning what the postures mean and how they affect their mother and litter mates. They learn what it is like to bite and be bitten, what barking and other vocalizations mean and how to make and use them to establish social relationships with other dogs. Such learning and activity tempers their own biting and vocalizing. From the age of five weeks, the mother teaches her puppies basic manners. They learn to be submissive to her leadership and what behaviors are acceptable. If necessary, she growls, snarls, or snaps at them as a form of discipline. When weaning the litter, for instance, the mother will discipline her puppies so that they will leave her alone. Because the mother disciplines them in a way that they clearly understand, after a few repetitions, the puppies will respond to a mere glare from her. If a pup has not learned to accept leadership (and discipline) in its early interactions with dogs, its training will be more difficult. Puppies that are removed from the nest too early tend to be nervous, more prone to barking and biting, and less responsive to discipline. Often they are aggressive with other dogs. Generally speaking, a puppy taken away from it's mother and litter mates before seven weeks of age, may not realize its full potential as a dog and companion. To maximize the mental and psychological development of puppies, they must remain in the nest with their mother and litter mates until seven weeks of age.

         Socialization Period (7 - 12 Weeks) It is at this age that rapid learning occurs. At seven weeks, puppies can learn and what they learn will have a lasting impact. Everything he comes in contact with will make a lasting impression upon him as it never will again. Not only will he learn, but, he will learn whether he is taught or not. Though he has a short attention span, what things he learns are learned permanently and resistant to change. Therefore, owners need to be careful about what their puppies are learning at this time. Your puppy is very anxious to learn how you want him to behave and react, and he needs to be shown what is expected of him in his new role as your pet. There are rules you will expect your puppy to obey. Establish those rules NOW while behaviors are easy to establish. For instance, how your pet interacts with you is determined during puppyhood. What he does now is what he will likely do later. So, don't allow your puppy to do things which will be unacceptable when he becomes a dog. During this time, you and your puppy will also begin to know and understand each other. You will get to know about your puppy's particular temperament and personality - whether he is strong-willed or eager to please, gentle or rambunctious, shy or outgoing, and just what else makes him the endearing individual that he is. For the puppy, this is both an exciting and somewhat confusing time. There is a whole new world of things to learn about and all sorts of new experiences to digest. Remember that the environments you put your puppy in are more complex than those he would encounter naturally. Puppies must now learn a new set of rules. He needs to know learn how to interact with humans and other animals who live with them. Puppies must adapt to the patterns and tenor of their new homes. All of these experiences and the behaviors which accompany them, must be learned. Because you will impose such important demands on your puppy, you must help him to make the transition into the human environment. You need to lay a groundwork for a trusting, happy mutually satisfying relationship. Keep in mind that puppies are less likely to broaden their experiences if they are insecure. In natural environments, puppies approach new things cautiously. By giving your puppy brief, repeated experiences in new situations, you give him a chance to become familiar. If you don't expose your puppy to a variety of situations and new environments, inappropriate ways to adapt may be learned. During the Socialization period, there is a fear imprint period from 8 - 11 weeks. During this time, any traumatic, painful or frightening experiences will have a more lasting impact on your pup than they would if they occurred at any other time. An unpleasant trip to the veterinarian, for instance, at this time could forever make your dog apprehensive about vets. To avoid this, take some treats and a toy with you. While you wait, play with your puppy and offer him treats. Have your vet give your puppy treats along with lots of praise and petting before and after the examination. Avoid elective surgeries, such as ear-cropping and hernia repair during this time. In general, avoid stressful situations. Remember, dogs are social animals. To become acceptable companions, they need to interact with you, your family, and other people and dogs during the Socialization Period. Dogs that are denied socialization during this critical period often become unpredictable because they are fearful or aggressive. It is during this time, that your dog needs to have positive experiences with people and dogs. Therefore, you need to socialize and teach your puppy how to interact with people and other dogs in a positive, non-punitive manner. You should gradually introduce your puppy to new things, environments, and people. But, care must be taken in socializing your puppy with other dogs or in areas where many "unknown" dogs frequent, prior to the time that your dog has had three of its booster vaccinations against contagious diseases. Shopping centers, parks, and playgrounds are good places to expose him. Begin by taking your puppy when there are few distracters. Give him time to get used to new places. Make sure he is secure. If you have children that visit only occasionally, have your puppy meet children as often as you can. If you live alone, make an effort to have friends visit you, especially members of the opposite sex so that your dog will become accustomed to them. If you plan on taking your dog to dog shows or using your dog in a breeding program, get him around other dogs. If you plan to travel with your dog, get him accustomed to riding in the car. Take him for brief rides, at first. Go someplace fun. Remember, if new experiences are overwhelming or negative, the results could be traumatic.

         Seniority Classification Period (12-16 Weeks) It is during this critical period that your dog will begin to test you to see who the pack leader is going to be. He'll begin to bite you, in play or as a real challenge to your authority. Such behavior is natural in the pack and not necessarily undesirable. What is undesirable is an inappropriate response on your part. It is important, at this stage, that you establish your position as pack leader, and not just another sibling. Other behaviors, such as grabbing at the leash, will be observed, and all are attempts to dominate you. Biting , in particular though, should always be discouraged. Therefore, you should not wrestle or play tug of war. Such play is aggressive-inducing. What you see as a fun game may be perceived by your dog as a situation in which he has been allowed to dominate. Wrestling, of course, communicates to your puppy that he is allowed to bite you. Tug of war sets you up in a dominance confrontation over an object. He learns that he can keep objects away from you. During tug of war games, puppies will often growl. Growling is a dominance vocalization, designed to warn another pack member that they better not confront the growler or he will bite. Puppies see these games as situations in which they have been allowed to dominate. They do not understand that these are games designed by humans to entertain them. You can continue to play with your dog during this period, but, the relationship between you during the play must change. No mouthing of your body should be allowed and when your dog does mouthe, you should respond with a quick and sharp "NO!" or "No Bite!" Play that does not get rough is best. If you cannot keep the dog from getting overly excited during a game and he persists in biting at you, don't play that way. This will only stimulate additional dominant behavior in the future. For these reasons, this is the stage when serious training should begin. Training establishes your pack leadership in a manner that your puppy will understand. By training your puppy, you will learn how to get him to respond to commands designed to show that you are in charge.

         Flight Instinct Period (4 - 8 Months) This is the age when puppies become more independent of their owners and are likely to venture off on their own. Puppies that have always come when called or stayed close to their owners will now ignore them, often running in the opposite direction. This period can last from several weeks to months. How you handle your puppy's refusal to come or stay with you will determine whether or not he will be trustworthy off leash. It is important to emphasize here that no puppy this young should ever be off leash except in a confinement area. Therefore, keep your puppy on leash when this period arises and keep him on leash until he readily returns to you or shows no inclination to leave you. The privilege of being off leash outside of a confined area, is reserved for dogs whose owners have trained them to the point where there is no potential for them to run and fail to obey to stop or come on command. Releasing an unleashed dog in an unconfined area that is not well trained off leash is irresponsible ownership and dangerous to your dog. Even well trained dogs can make mistakes or become distracted by something in the environment so that they do not respond to their owners' commands. So, how do you respond when your puppy suddenly develops the urge to bolt? First, you must, for his safety, put a leash or a long line on your dog whenever you are not in a confined area. Second, work hard on training your puppy to come on command. Use the recall game and the spontaneous recall. When walking your dog, suddenly run backwards and encourage your puppy to come. If your dog still continues to bolt or run away, then your dog probably does not view you as the dominant figure in this relationship and you require special help to resolve this problem. Even if the your puppy appears less inclined to bolt, this does not mean that he is reliable off lead without more maturity and a lot more training.

         Adolescence Period (5 - 18 months) Adolescence can appear in smaller dogs as early as five months. In larger breeds, it can start as late as nine or ten months. In giant breeds, adolescence doesn't take place until twelve to eighteen months. In general, the larger the dog, the longer it will take to physically mature. Some breeds can remain adolescents until they are two and a half, or three years old. Adolescence is expressed in male dogs by scent marking behavior. Scent marking behavior is stimulated by the release of testosterone into the dog's system. At this time, males may become macho. Male dogs may become less friendly and even somewhat aggressive to other male dogs. He may begin lifting his leg in the house. He may become very interested in girls, tend to roam, and certainly not interested in listening to you! Some males at this age become totally unruly. In females, adolescence is marked by the onset of the heat cycle, estrus. During this three week period, your bitch could become pregnant. So, keep her away from all male dogs. Bitches exhibit erratic behavior during estrus. Some get real moody and insecure. Others become quite bold or even aggressive. Adolescence is a very difficult time for pet owners. They are surprised when their cute little puppy becomes a free and independent thinker. Adolescence is certainly a good time to start (or reinstitute) rigorous training. You must work hard NOW to mold the dog of your dreams.This course will teach you training methods which are based on sound knowledge of dog behavior. You will gain knowledge about dog behavior and training techniques. This knowledge will help you to get through your dog's adolescence. A dog that you iew as too stupid, too old or stubborn or too spiteful can become a well mannered, enjoyable, and reliable companion. Establish yourself as the leader of the pack. Be realistic about your expectations.You cannot expect young dogs to grow up overnight. Learn to appreciate your dog's adolescence for it is a truly wonderful time. At this time of their lives, dogs are very energetic and exuberant in their responses. They can be full of beans, but still, delightful playmates. You as the owner must learn to channel that energy and exuberance into learning, working, exercising, and playing games. It is not too late to to train (or retrain) your dog to help him to become a long-lasting companion.

         Second Fear Imprint Period (6 - 14 Months) The Second Fear Imprint Period is similar to the one that occurred during the socialization period, but, it is much less defined. It occurs as dogs enter adolescence and seems more common in males. It is often referred to as adolescent shyness. Your dog may suddenly become reluctant to approach something new or suddenly become afraid of something familiar. This behavior can be very frustrating to the owner and difficult to understand because its onset is so sudden and, seemingly, unprovoked. If you notice this behavior, it is important to avoid the two extremes in response: Don't force him to do or approach something frightening to him and don't coddle or baby him. To get through situations that make your dog fearful, be patient, kind, and understanding. Desensitize him to the object or situation by gradually introducing him to it and using food rewards and praise to entice him to confront the fearful object or situation. Do not coddle or reassure him in any way that will encourage his fearful behavior. Do not correct him either. Simply make light of it and encourage him give him food rewards as he begins to deal with his fear better. Make sure you lavishly praise his attempts! This phase will pass.

         Mature Adulthood (1 - 4 Years) During this period your dog may again become aggressive and assertive. For instance, he may become more turf-protective, by barking when someone comes to the door. Temper his protective behaviors by teaching him how to accept strangers into your home. His friendly play with other dogs may escalate to fighting with other dogs. Teach you dog to ignore other dogs that he sees if he can't be friendly towards them. Take him to places where there will be a few dogs at first and train him there. Then, train him in areas with more and more dogs. Next, allow him to interact with non threatening dogs. Puppies and bitches are good choices, if he is a male. Always praise his positive efforts to interact or if he displays no reaction. Gradually move onto male dogs. At bit of caution here, adult members of the same sex, no matter what animals species, tend to compete with one another. Putting together two strange adults of the same sex could result in a fight. Watch for behavioral signs of playfulness before allowing two dogs to play together. Also, be alert to the posturing of aggressive behaviors. Watch for circling behaviors, walking on toes, stiff tail wags, and tense facial expressions. Adulthood is also a time that your dog may again test your position as pack leader. If he does, handle him firmly, suspend any rough play that may be giving him the idea that he can dominate you, and continue with training. Additional classes or private help with training may be a wise investment. It can provide you with the structure and commitment to train him that you need at this time. Proceed with training in a matter-of-fact, no nonsense manner and your dog will become a reasonably obedient dog. Give him lots of positive attention for his efforts!

         Closing Remarks This has been a cursory look at some of the behavioral changes that often occur during puppyhood, adolescence, and early adulthood. Other problems may arise at these stages which are not the result of the developmental period itself, but are caused by something in the environment or the dog's basic personality. Even so, they are probably aggravated by immaturity and you cannot afford to overlook them. Understanding, training, and perhaps professional help with training are the keys to success. All dogs are different. Some will not exhibit the behaviors we have discussed and others will pass through them at varying rates with smaller dogs maturing faster than large dogs. Remember that your dog needs you to play a role in his development and you can do that with knowledge and commitment to training. Learning plays a significant role in a dog's development. Through training, you actively take part in that process. This course has been carefully designed with the capacities of developing dogs in mind. Throughout the course, you and your dog will be observed. You will be advised if your dog exhibits behaviors which may be warning signs of potential problems. We will teach you exercises which will help your dog to be a good companion. The exercises your dog or puppy will learn should not tax him. Learning can be fun and each dog can achieve success.

Puppy Growth, Behavior and Development
This section details information regarding Puppy rates of growth and development according to the age of the puppy. Each stage of puppy growth charts invaluable info about a puppy, what to expect and how a puppy should be treated. By the time it reaches its first birthday a puppy is considered a mature, adult dog. Puppy Growth rate is fast compared to humans, just compare a puppy of 8 weeks to a baby of the same age. Each stage of Puppy Growth and development is fascinating and it helps to understand each stage a pup will through to reach adulthood.

Growth Rate - Adult size of a puppy
One of the most common questions asked about a puppys growth and development rate refers to the eventual size of the puppy. How big will the puppy grow? How can you determine the adult size of a puppy? It is easy to get completely carried away when choosing a puppy. A young puppy is tiny and cute - everyone loves puppies! But will the puppy be suited to your environment? How much exercise will be required for a full grown dog? Will the puppy be a suitable pet for children? The breed of the puppy will determine the answers to these questions. A general response to the size and growth rate of a puppy and the adult size of a puppy is therefore not possible - it needs to be specific to the puppys breed. This important information has been addressed via the breed section of each puppy. A size comparison picture has been provided for each different type of dog. The picture shows an adult dog next to a man and a woman - thus establishing the eventual adult size of a puppy. This is the only site on the internet that provides this critical information by a visual representation! Please click the following link to check out the growth rate in terms of size for you individual puppy breed!

Stages of Puppy Growth and Development
The following sections detail the various Growth and Development stages up to 1 year old with puppy behavior details:

Newborn Puppy Growth and Development & Behavior up to 3 weeks

  • A puppy is born blind, deaf and toothless
  • During its first week 90% of a puppys time is spent sleeping and 10% eating. They are only able to crawl
  • The puppy's eyes, which are closed at birth, open when it is between one and two weeks old. It then begins to see
  • The pups ears should open when it is two to three weeks old
  • Puppies whimper when they are cold, hungry or uncomfortable
  • Puppys grow while they sleep
  • A puppy is reliant on its mother for the first few weeks for food, comfort and to learn basic dog requirements

Puppy Growth and Development & Behavior between 3 to 7 weeks old

  • A puppy will be weaned between the ages of 3 and 7 weeks
  • During the ages of 3 to 7 weeks its first teeth, or milk teeth will appear
  • A puppy is taught basic behaviour disciplines from its mother
  • A puppy will continue to develop by socializing with other dogs and animals and people
  • Puppies will stand up and start walking
  • At the age of 3 weeks a puppy will develop its sense of smell
  • At 3 weeks the puppy will begin to bark and show social development such as wagging its tail, growling and baring its teeth
  • Up to the age of 4 weeks the mother will be with the puppy almost constantly
  • The puppy has good use of its legs and is able to chase
  • Between 4 and 5 weeks the mother will gradually spend time away from her puppies
  • Rapid growth and development rate at this stage
  • Interaction with litter mates leading to Order of Dominance
  • After weaning puppies need to receive a series of vaccines in order to develop immunity on their own. Vaccinations for puppies generally include distemper, hepatitis, leptospirosis, parainfluenza, parvovirus, rabies, and sometimes bordetella

Puppy Growth and Development & Behavior between 7 and 12 weeks

  • Puppies are usually found new homes at this age it starts focusing attention on its owner rather than other puppies
  • The first fear period of the puppy begins
  • A puppy starts to learn it name but still has a short attention span
  • The puppy will start house training
  • At first, the puppy should be fed four times a day. (Feedings should be reduced to twice a day by the time a puppy is mature or even once a day in the case of a dog that gets little exercise)
  • The puppies motor skills improve
  • The puppy will use its basic instincts to naturally explore its new environment and the different things within it
  • Puppies will still sleep a lot and grow as they are sleeping. During times of stress, a dog raises its hackles - the hair along the neck and spine
  • Puppy training must begin and pups need to be made aware of your rules

Puppy Growth and Development & Behavior between 12 and 16 weeks

  • The first of the permanent teeth will work through
  • Ensure the puppy has plenty of attention and toys to play with
  • At this age a puppy might demonstrate Pack Leader Behavior and test who is the Boss. A puppy will challenge your authority

Puppy Growth and Development & Behavior between 4 and 8 months

  • The adult teeth continue to come through and during this time puppies need to chew! The incisors and the canines are very important because the dog bites and tears at its food with these teeth
  • Provide them with items to chew
  • The confidence of the puppy will now have grown as would its physical size
  • The puppy will be showing interest in chasing other Puppies at this age and starts to become independent

Puppy Growth and Development & Behavior between 8 months to 1 year

  • Feeding frequency should be considered - reduce to 2 or 3 meals per day
  • Some dogs reach sexual maturity at the age of eight months
  • The puppy is old enough to start Obedience Classes or a professional training program
  • The puppy would have grown to approximately half to three quarters the size of and adult
  • Female dogs would have probably reached their eventually height but will to continue to 'fill out'

Growth and Development & Behavior - 12 months old
Puppies are now considered to have finished their development and growth rate and are viewed as adult dogs.
Although sexually mature beforehand, a dog usually does not attain full growth until at least its first birthday.

Puppy Growth - Large Breeds
The information provided on this page relates specifically to the various stages of Growth and Development & Behavior you can expect to see in your puppys first year. In respect of the larger dogs, such as the Mastiff, caution must be taken during growth periods in the first 18 months of the puppy's life. Excessive exercise such as jumping obstacles or over long walks can cause joint damage.

Terms we all need to know as breeders

Aspirate: Withdraw fluid or cells through the use of suction - usually the suction produced by pulling back on the plunger of a syringe attached to a needle which is inserted into the area to be sampled.
Colostrum: The antibody-rich first milk produced immediately before and after giving birth.

Conception: The onset of pregnancy, when the fertilized egg attaches to the uterus.

Congenital: A characteristic of an animal that is present at birth. It may be inherited or induced by events that occur during pregnancy.


Diestrus (also Diestrous): The stage of the estrus cycle which occurs after the animal goes out of heat


(Canine) Distemper: A viral disease that caused a severe and often fatal systemic illness in dogs and their close relatives. Distemper is also fatal in animals such as raccoons, and mustelids including skunks, mink and ferrets.

Domestic Animal: An animal that has been housed and fed by man for generations and has little fear of man as a result. Some domestic animals learn to depend on human provision so completely that they have little ability to survive if returned to a natural habitat.

Dystocia: Difficult birth.


Estrogen: A female hormone produced by the ovaries, which results in the onset of estrus.

Estrus: The time when a female animal is fertile and receptive to the male. Also known as a heat period.

Heartworm: A species of parasitic worm that lives and reproduces in the chambers of the heart of an animal. Microscopic, immature worms (microfilariae) circulate in the blood and are taken in by mosquitoes that bite the animal. Microfilariae mature in the mouthparts of the mosquito and infect another susceptible animal bitten by the same mosquito.

Hepatitis: An inflammation or infection of the liver.


Hernia: The protrusion of an organ through an abnormal opening.

High titer vaccine: A modified live vaccine that contains a higher number of virus particles than the 'average' vaccine. High titer vaccines can generally elicit an immune system response in young animals who have a maternal antibody level that would prevent them from responding to an 'average' vaccine.


Lactating: Producing milk.

Mammary: Pertaining to the breast.



Mastitis: An infection or inflammation of the mammary glands.

Maternal antibody: Antibody in a newborn animal which the newborn acquired through the placenta or colostrum (the first milk).


Neuter: Sterilization by surgical removal of the testicles of a male animal.

Ovulate: The release of an egg from the ovary of the female.

Palpation: To examine with the hands or fingers.

Parturition: act of giving birth.

Passive immunity: Immunity produced by providing an animal with antibodies or immunologic cells from another source, such as colostrum. Compare with 'active immunity'.

Pathogenic: Causing disease



Proestrus (also Proestrous): The stage of the estrus cycle, right before an animal comes into heat.

Progesterone: A hormone produced by the ovaries which is responsible for the continuation of pregnancy.



Prolactin: Hormone secreted by the pituitary gland that stimulates the growth of mammary tissue and the production of milk.


Pulmonary edema: Fluid accumulation in the lungs


Pyometra: An infection of the uterus.

Queen: A female cat used for breeding.

Queening: In cats, the act of giving birth.

Rabies: A fatal virus disease of warm blooded animals including man, that affects the brain and is spread in the saliva of infected animals. Rabid animals have a temperament change. Wild creatures become bold enough to attack human beings, and docile domestic animals may turn on their owners.


Resorption: In pregnancy, a condition in which the fetus dies, and instead of being aborted, the fetal tissue dissolves within the uterus and is absorbed by the mother. The mother will show no outward signs of a fetal resorption.

Respiratory depression: Decrease in the rate or depth of respiration.

Spay: Sterilization by surgical removal of the ovaries and uterus of a female animal.

Sphincter: A ringlike band of muscle that constricts a passage or closes an opening, e.g., the anal sphincter constricts to close the anus and relaxes when the animal is passing stool. The urethral sphincter closes the urinary bladder.

Subcutaneous:Under the skin; often called 'sub Q' vaccine

Titer: A measurement of the amount of antibodies in the blood. The test to measure antibodies is usually performed by making a number of dilutions of the blood and then measuring at what dilution there is sufficient antibody to react in the test. For example, a titer of 1:8 (one to eight) means the blood can be diluted to one part blood and seven parts saline and still produce a positive reaction in the test. The higher the titer (1:16 is higher than 1:8), the more antibody is present. (NOTE: The word 'titer' may also be used when discussing the amount of antigen present, e.g., a high titer vaccine has a large number of virus particles.)

Ultrasound/ultrasonography: A technique used to get the image of a deep structure within the body by directing ultrasound waves at it and recording the reflections (echoes) from it.

Umbilicus: The area of the body where the umbilical cord is attached; the belly button.

Vaccination: The act of giving a vaccine. See also 'immunization' since the two words have different meanings and are often confused.

Vaccine failure: A term often used to describe a condition in which an animal who was vaccinated against a disease still gets the disease. In truth, there is usually nothing wrong with the vaccine, but for some reason the animal's immune system did not adequately react to it.


Window of susceptibility: A time period in the life of a young animal in which the maternal antibodies are too low to provide protection against a certain disease but too high to allow a vaccine to work and produce immunity.

Zoonotic: A disease which can be transmitted between animals and people.