Patricia McConnell Seminar: What Science Tells Us About Puppy Development

So now we know: a dog's behavior is a complex thing, based upon both his genetics and his experiences. But can we stack the deck in our favor? How do we ensure that our dogs, and those in the future, are safe, healthy, and sound? What do we know, scientifically, about puppies? Patricia shared some of the research (and some of her own opinions) on the matter.

Good Dogs Start Before They're Born
If genetics influences behavior, that begs the question: What are we breeding for? Patricia showed us a slide that was made up of advertisements for various breeders, including show/conformation breeders. The focus was unequivocally on physical characteristics: size, substance, toplines, coat, color... things which are easily visibly, but in the grand scheme of things, probably not so important, at least not when we're considering the family pet.

The thing is, Patricia told us, today's breeds have severely limited gene pools, and while this is great for establishing a breed, it tends to be detrimental for maintaining it. Lack of genetic diversity can result in less variability in major histocompatibility, which is related to autoimmune diseases, allergies, and hypothyroidism. Patricia urged breeders to calculate co-efficients of in-breeding rather than just looking at pedigrees, and for breed clubs to consider outcrosses with related breeds when done to introduce new genetic material. As for us puppy buyers? We need to look for breeders who consider temperament when planning litters.

Maisy is from a puppy mill- and it shows, even at 12 weeks.

But there are other things that affect a puppy even before he's born. His in-utero experiences can have an effect as well. If a puppy’s mother is experiencing stress, she will have higher levels of cortisol in her body, which will probably reach the fetus. If it does, the fetus will develop fewer brain receptors for cortisol. As an adult, that puppy’s brain won’t be able to sense cortisol unless there are large amounts present in the body. Since the body does need some cortisol, the brain will compensate for the lack of receptors by producing increased amounts, which can result in hyper reactivity, withdrawal, and depression. Not a good thing, and it definitely puts a whole new spin on puppy mills, doesn’t it?

But even if momma dog is happy and content throughout her pregnancy, the number of male vs. female pups in the uterus can have a profound effect on behavior through the process of androgenization. This happens when a female fetus is next to or between two males, which will expose her to increased amounts of testosterone. Studies have found that testosterone has been correlated with an increase in cortisol and aggression. Of course, we really can’t control things like who is next to whom in the womb, but it’s still interesting!

Help Puppy Be All He Can Be
A puppy’s early days can also have a profound impact on his adult behavior. And I do mean early- the US Army created an Early Neural Stimulation program (also known as SuperDog or Biosensor) that is completed between days 3 and 16. This program only takes a few minutes a day, but the end result is impressive. The Army’s research shows that it results in dogs with stronger heart beats, a better adrenal system, increased immunity, and more stress tolerance.

"What is all this white stuff?!"

The results are probably the result of increased dendritic branching. Dendrites are basically connections to other neurons, and when there are more connections, the dog will have increased health and mental stability. Dendritic branching happens as a result of experience, and so things like the early neural stimulation programs probably increase the amount of dentritic branches in the puppy’s brain. Another easy way to do this is by providing a complex environment for the puppy to explore (play tunnels, platforms, different surfaces); such novel experiences help improve the puppy’s long-term behavior.

Nursing is also a vital experience for puppies. Patricia described how pups will push their littermates off a teat, which teaches frustration tolerance and persistence. The pups also learn to tolerate a lot of body touching/handling when this happens. This is probably why, anecdotally, puppies from single litters seem to have more behavior problems.

Patricia also advocated for allowing momma dog to do a natural weaning instead of the breeder forcing weaning at a particular age. In addition to teaching frustration tolerance, she’s seen some very interesting body language happen between momma dog and puppies, and believes that this process is an important learning experience for the pups.

Socialization, Puppy Classes, and You
Anyone who has been in the dog world, even peripherally, has probably heard about the importance of socialization. But what do we know about it scientifically? Well, the results are interesting… and not entirely what I expected.

First, when is the socialization window? Well… we don’t really know. Scott and Fuller said the primary socialization window is between 3 and 7 weeks, but were willing to extend it out as late as 12 weeks. Patricia described some of their research as “squishy,” which means that she takes those ages with a grain of salt. Add in the fact that every individual will develop at his or her own rate, and… well, there's science there, but it's not an exact science.

Okay, but what can socialization do for a dog? Well, two separate studies, conducted on two different breeds, found that socialization may help in some areas, but that it’s unlikely to create a difference in adult dog’s attitudes towards people. One project on German Shepherds studied the differences between puppies adopted at either 6 weeks or 12 weeks, and found no difference in either group in their adult behavior towards humans. However, the pups adopted earlier showed higher distress behaviors, disease and mortality. The other study grouped Jindo dogs into two groups: half were socialized from weeks 7 to 13, and half were isolated. The results showed that the socialized dogs were more playful towards novel objects and dogs… but that there was no difference in their attitudes about people.

So what does this mean? Well, it’s possible that the socialization window is open longer than the guidelines suggest. It’s also possible that a dog’s behavior towards people is more strongly linked to genetics (and less so to early experience) than we think. Considering the fact that dogs have been selectively bred for hundreds of years to interact with humans in certain ways (cooperatively to herd, independently to kill pests, etc.), this seems plausible. Ultimately, we don’t know how much of an effect socialization has, although it seems clear based on the Jindo dog study that even if the benefits are more limited than previously thought, it’s still worth the time.

One highly touted way of socializing puppies is through puppy classes. But does science back this up? Well… probably not. Some researchers placed 58 pups into 5 different groups: socialization and training, socialization only, training only, going into the classroom and being fed a comparable amount of treats, and going into the classroom and having nothing happen. The end result? They found that the group the puppy was placed in had no effect in their social responses to people or other dogs.

Maisy went to puppy classes... but did it matter?

What they did find, however, is that the dogs in the socialization and training group were rated higher on responses to obedience commands, and a later study done by MM Duxbury (who just so happens to be my dog’s own veterinary behaviorist) found that dogs who went to puppy classes were retained at higher rates (90%) than those who did not (75%). Was this because of the effects of socialization? Were these dogs more obedient, and thus easier to live with? Did the owners simply bond with their dogs more if they’d been through a class together? Or was there actually some socialization going on that "innoculated" the dogs against future behavior problems? No matter the reason, it would seem that puppy classes are not a waste of time.


So… can we stack the deck in our favor? Probably, although I suspect we just don’t know enough just yet. Still, it is exciting to see that there’s a lot of research being done into dogs in general, and puppies in specific. I am grateful that I had the opportunity to hear Patricia McConnell discuss some of it.

If You Want to Know More

• MHC class II polymorphism is associated with a canine SLE-related disease complex, an article by Wilbe, et al
• Low Uric Acid Dalmations, the website for the most famous outcrossing project to bring in genetic diversity, and a project cited by Patricia in the seminar
• My own post on Transgenerational Epigenetic Inheritance (Not recommended by Patricia, but there are a lot of cool links here.)
• A link to a Google Books excerpt from Steven Lindsay’s Handbook of Applied Dog Behavior and Training, which has a discussion of Beach’s 1982 study on testosterone in dogs.
• Information on testosterone’s effect on the brain, from the University of Plymoth
• The Social Endocrinology of Dominance: Basal Testosterone Predicts
  Cortisol Changes and Behavior Following Victory and Defeat, a study by Mehta, et al
• Information on the Army’s Biosensor program
• Scott and Fuller’s book, The Genetics of Social Behavior
• The effect of early separation from the mother on pups in bonding to humans and pup health, by Slabbert and Rasa
• Behavioral Reactivity of Jindo Dogs Socialized at an Early Age Compared with Non-Socialized Dogs, by Kim et al
• The Seskel puppy class study is summarized on page 7 of this document
• Dr. Duxbury’s study on puppy classes