Environment, Genes
and Mental Hygiene

Latest research could prove to be food for thought for breeders

by Pernille Monberg

It is common knowledge among dog breeders and owners that in order to breed and/or obtain dogs who are mentally stable one must choose breeding stock with good temperaments. It is also common kowledge that, as soon as the puppies open their eyes and are able to hear, outer stimuli will play a large role in the final result. Some of us have perhaps heard old-time breeders say that puppies inherit temperament from the bitch. This is something that I have always just brushed aside as being an old wives tale, but perhaps the old timers weren't as far off target in their claim after all. Perhaps the very early mother/pup interaction has a greater significance on the social development of the puppy than previously assumed.

Kennel management and maternal care

Back in 1992 I visited a large Kennel for Irish Wolfhounds on the American continent. At the time of my arrival the breeder had a litter of three week old Wolfhound puppies. Much to my surprise, the puppies were alone in the whelping box in the kitchen. Their mother was only allowed inside to feed the puppies a few times during the course of the day. As soon as they had completed their meal, she was removed again. When the puppies were 4 weeks old, she was allowed to see them once a day. During the two weeks I spent with this breeder, the mother and puppies had no other form of interaction than the feeding/sucking. The breeder told me that she usually sells her puppies at the age of 6 weeks, as this ensures the closest bond between owner and dog. To this I must add that I have later learned that her dogs are known to have a difficult time handelling stress situations outside of their home environment. It is a question whether it is a result of a genetic inheritance or a result of the mentioned environmental factors.

At the time of my visit I assumed that her kennel management was quite unique. However, over the years that followed, my travels have brought me loads of first hand experience with regard to how breeders manage their whelping bitches and the care for the pups. I have seen and heard that many, many breeders of large dog breeds do indeed remove the bitches from their young for shorter or longer periods of time during the course of the day and/or the night. They do so simply because they are afraid that the bitch will trample on or lay on the pups and kill them.

Having a litter of puppies of large breeds is an enormous 24/7 workload for the breeder. Removing the bitch once in a while gives the breeder some free time on his or her hands or will ensure a good nights sleep. Frankly I can't understand how this can be done. My bitches have always gone berzerk if I have removed them while cleaning up the whelping box. The separation seems to cause unnecessary anxiety in the bitches, which is counter to the calm environment that should surround the developing puppies. Seperating mother and pups ensures the comfort of the breeder, but certainly may not be in the best interest of the bitch.

I have also learned that many breeders have chosen to wean their puppies off the bitch as soon as they are eating solid food, which is when they are about 3 1/2 - 4 weeks old. What exactly are the consequences of these approaches to the care of the domestic dogs and their pups?

The 4 physical and mental developmental periods of dog pups

According to researchers Scott and Fuller (1965), the physical and behavioral development of dog puppies can be divided into four periods: (1) The neonatal period, from birth to the age of eye opening; (2) the transition period, from the age of eye opening to twenty days; (3) the period of socialization, from twenty to about seventy-seven days; (4) the juvenile period, from twelve weeks to maturity.

In the following I have chosen to concentrate on the time which the majority of puppies spend with the breeder, namely the neonatal period, the transition period and part of the socialization period. I have done this because this is the period where the puppies are still with their mother being prepared for the lives in their new homes. For the domesticated dogs, the juvenile period is a time where they have been sold off and are therefore no longer under the influence of the mother.

Neonatal puppies are blind and deaf and their needs are very fundamental: they need warmth, milk, and they are dependant on their mothers licking of their anal/genital region for the excretion and elimination of bodily waste. They do not overtly react to other outer stimulous, which is why it is commonly assumed that the actual imprinting and learning of social skills does not start until the transitional phase. There are nevertheless behavioural scientists who claim that the mothers licking, especially in the anal/genital region, also plays a significant part in the early imprinting of important aspects of adult behaviour, namely passive submission. An adult hound exhibits passive submission by rolling over on its back, baring throat and stomach, and allows a more dominant dog to examine or lick its genital area. The submissive dog will often excrete a bit of urine, just like the neonatal pup when the mother licks it.

The latest findings in behavioural science

In the beginning of June 2003, a conference was held on the topic: fetal and infant origins of adult disease. The latest findings by Dr. Michael Meaney, Professor of medicine at McGill University in Montreal, Canada was presented at the conference. Meaney's data showed that baby rats which were licked by their mothers often turned out to be less anxious and fearful as adults and produced lower levels of stress hormones than those who were groomed less. In other words, the rechearchers discovered that the maternal care literally caused the infants brain to "crank up" a gene which fullfills the task of calming the the individual in stressful situations.

Meaney's material is based on 100 mother rats and their progeny. The researchers selected 50 females who provided lots of maternal care in the form of licking and grooming of their young, and 50 females who provided 4-5 times less grooming and licking. The aim of the research project was to observe and measure if the maternal care of the infant had long term effects on the individuals behaviour later in adult life.

Stress hormones

In the brain you have different receptors. One type is for stress hormones such as cortisol. The greater the number of receptors, the better the brain will be able to register how much cortisol is released by the body in stress situations, and finally be able to inform the adrenal glands when to stop sending out the hormones. The number of receptors simply decides how well the body responds to stress.

"The receptors are made by genes. The gene was more active in adult rats who were reared by high-licking mothers than in those raised by low-licking mothers," Meaney said.

DNA from progeny of both groups (50 from each) was then examined, and it turned out that one particular gene proved to be more active in producing cortisol receptors in the group of highly licked and cared for baby rats than in the group of young who did not recieve the same care. To ensure that these differences were indeed brought on by the quality of maternal care and not just the result of a genetic pre-disposition, another group of baby rats were switched around. Now babies of the high-caring mothers were placed with mothers who provided less maternal care and vice versa. The result was that the babies who recieved the optimal maternal care regardles of their biological mothers were still producing a higher number of cortisol receptors than the group whose foster mothers provided less maternal care.

In a final experiment the researchers entirely removed the mothers and instead stimulated the babies with paintbrushes. The result was in agreement with previous findings: the babies who recieved the most touching and stroking with the paint brushes developed more cortisol receptors than the group who were touched less.

One should naturally show caution in drawing conclutions on one species based on research performed with another species. In the presentation of the project, it was clearly pointed out that it was still uncertain whether the findings were directly applicable to human maternal care and the baby's later ability to handle stress. Rats are born blind which presumably makes them more sensitive to touch, while human infants are born into a more complex environment with a wider spectrum of sensory stimuli. What makes Meaney's findings interesting for dog owners, especially dog breeders, is that neonatal maternal care in rats and dogs are much more similar than in rats and humans. Both baby rats and dog puppies are born blind and deaf . Nevertheless, based on the latest findings, the experts still believe that the fundamental principles are pretty much the same across the species.

"This is a very important study. It's fabulous data -- really world-class," said Peter Gluckman, a professor of pediatric and perinatal biology at the University of Auckland in New Zealand, who was not involved in the research. "It shows us that the expression of genes in mammals can be permanently changed by how mothers and infants interact and how that can have long-term effects on behavior and psychiatric health."

The bitch usually knows best

As soon as the puppies have opened their eyes and are able to hear, their mental development seems to accelerate. They soon begin showing interest in their mother's food. The interest in food is directly proportional with the milk production. In small breeds the interest in food occurs later than in larger breeds. Litter size is also a determining factor. Small litters survive longer on mothers milk than larger litters. What can appear paradoxical is that the mother will growl at the puppies if they attempt to eat her food, but many bitches will regurgitate the same food in order to feed the young. There are two possible explanations for this behaviour. First she is teaching them a very important social skill, which they cannot be without if they are to live in a pack. This is the dog-rule which says that a dog must never take food, bones or any object from another dog as long as the owner of the object has an interest in his posession. Puppies know this from a very early stage. Even when this rule is broken, it is usually done so with various forms of trickery indicating that the perpetrator is well aware of the illegality of what he intends to do. This fundamental dog-rule seems to transgress any social order. I have often witnessed a high ranking elder sniffing a bone or a prized-posession of a small puppy, who without moving his head will let out a deep growl in return. 99% of the time, the elder will respect the little one's right to his property and leave him alone. Another possible explanation for the mothers' guarding of their own food against the young pups, and later regurgitating it for the pups, could be that it is easier for the pups to eat food which is either partly digested or at least contains digestive enzymes from the mother.

The bitch's role remains very important, even after the puppies are eating solid foods. She is instrumental in teaching them the fundamental social skills. For the novice dog breeder, this mother/pup interaction can appear paradoxical and quite rough. She will seek out a puppy and seemingly harass this pup into submission, while at the same time fiercly protect her pups from the other dogs in the pack. It is extremely important that the puppies learn submission before they set out into the world. The submission has a calming effect, stating that a dog poses no threat, and can save him from having to involve in physical conflict.

Socialization gone wrong

The following is an example of how terribly wrong things can go, due to the owner's ignorance. An inexperienced breeder calls her veterinarian and ask: At what age can one equip puppies with a muzzle? The breeder had a litter of puppies aged 7 or 8 weeks. The interaction between the littermates went far beyond the normal playing, fighting and testing of limits which puppies do at that age. These puppies had never been allowed to establish a social order, nor had they been allowed to learn the importance of submission from their mother. The owner had intervened and stopped any learning of basic social behavior. The owner thought that she was protecting the puppies. As they grew older they became progressively more aggressive towards one an other. The owner of the litter called the veterinarian at the point where the puppies could no longer be left together. They had to remain seperated, otherwise they would have killed each other. The problem was probably solely due to the owner's counterproductive interference with their natural social training and development. I have later learned that the puppies had to be euthanized, as they had developed into complete social misfits which could not safely be placed in new families.

Some years ago I purchased an 11 week old male pup. He grew up with two bitches of approximately the same age, and the three of them formed a juvenile group within my pack. They played and hung out together 24/7 -- they were inseperable, and pretty much left alone by the older dogs. Not until the young male was about 1 1/2 years old did I discover that something was strange in his behavior. He was not fully capable of functioning in a pack, as he lacked one very important social skill: he did not know submission. He was never a very assertive or in other ways dominant dog so I guess situations where this was exhibited did not really occur until he became sexually mature and had a couple of run-ins with the older males. He has made no attempt to dominate or take over, but reacts with a frightened growl when told to get out of the way by another dog. It is almost as if he is unable to read and interpret signals from other dogs and he is also the only dog I own who doesn't seem to try to read human facial expressions. It is almost as he resides inside a bubble, completely unintegrated in the pack. I have a suspecion that something has gone wrong in the very early stages of his life, most likely having to do with the mother/pup relationship, rather than the between the pups of the litter.

Well functioning puppies

Many of us have probably had the experience of visiting some breeder where puppies, cats and human children roam around in the kitchen in "neck-breaking exercises." We have probably let out a deep sigh and thought; this will inevitably have a disastorous outcome. Toddlers who can barely balance on their own two feet stomp around with a puppy dangling from their arms, and do so without the adults interfering. Those who have experienced bringing a puppy home from such a place will often have to admit that this puppy is completely unimpressed by meeting the World. Puppies reared in such an environment are touched, played with, and exposed to all sorts of nioses and other experiences to the point where (if they survive the human children) nothing can startle them. I would however never recommend letting children handle puppies unsupervised by adults.

It is not my intention here to underestimate the individual's genetic pre-disposition for stress management and temperament. I am convinced that it is still important to select breeding material from criterias such as mentality along with all the other factors which we have to take into account as breeders. It is none the less equally important to acknowledge that many, many other factors play a part in the development of the psyche of the individual. With Dr. Michael Meaney's latest findings, breeders just may have to acknowledge that they play a much larger part, and have an even bigger responsibility in the psychological development of their dogs than generally presumed, which is worth taking into account when setting up the environment for bitches and their puppies.


Coren, Stanley , 2001, "Tal Hundsk" translated from English "How to Speak Dog Mastering the Art of Canine Communication" Danish edition:
Borgen, Copenhagen

Mech, David L. 1995 (1970) "The Wolf. The Ecology and Behavior of an Endangered Species"
University of Minnesota Press. Minneapolis, USA

Meaney, Michael Phd. Quoted In: Associated press. June 9th., 2003

Scott, Paul & John L. Fuller 1965. "Genetics and the Social Behavior of the Dog"