Side Effects Continued

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Working Environment

Training and handling aside, performance event titles may or may not indicate a strong genetic predisposition for the behavioral traits typical of a breed’s original purpose. How true-tolife is your chosen competitive arena? The more true the better it serves as a test of the innate behaviors required to fulfill the breed’s purpose. The Border Collie’s open field sheepdog trials are very like the actual work the dogs were first bred to do.

In contrast, in a Schutzhund blind search the dog needs to find the guy with the stick and the padded sleve, just as a police dog needs to find the bad guy. Any well-trained Schutzhund dog is smart enough to know that the guy is always behind the 6th blind but it’s his job to search the other five first. On the other hand, police dogs, whose daily task is the real work upon which Schutzhund and similar sports are based, must think for itself and ignore the handler’s commands if it knows the handler is wrong. Real bad guys are often armed with more than a stick and won’t hold fire while the dog searchs “empty blinds.”

Alaskan Huskies are the breed of dog that dominates competitive sledding events. They are bred solely for their racing ability and are not restricted to a closed breeding pool; breeders occasionally employ crossbreeding to improve performance. This practice was typical in purposebred dogs before the era of studbooks and kennel clubs. A genetic study of Alaskan Husky performance in both short- and long-distance races published last July revealed that researchers could distinguish sprint dogs from distance runners by their genetic profiles. Admixture of genes from dogs of the hunting group could be found in successful sprint teams while dogs whose profiles revealed arctic heritage were better at the endurance events.

Without a thought…

Sometimes we wind up making breeding decisions without any conscious consideration of what we are doing. A number of years back a study of market hogs revealed that hog farmers who raised large numbers of animals inside barns and their colleagues who pasture-raised their stock inadvertently selected for different dispositions. All hogs in the study were of the same breed, but the barn raised animals were much less aggressive. Since excess aggression can be a managementnproblem in a high-density environment, those farmers tended to keep less aggressive animals for breeding simply because they were easier to
manage. Over time and generations this had a measurable effect on the animals’ disposition as opposed to that of their more traditionally raised cousins.

It is very probable that dog breeders do the same thing. A dog whose behavior does not suit your particular circumstance isn’t likely to remain in your home or kennel. Similarly, in a wide variety of breeds the divergence we see, not only in behavior but in body morphology, between working/field and show strains is in part influenced by the differing circumstances surrounding each set of breeders’ approach to dogs and dog breeding. For example, Australian Shepherds were once all ranch dogs whose ability to guard the home, ranch buildings and their owners’ pick-up trucks was as highly valued as their utility in managing livestock. Today, most Aussies live in urban or suburban environments where a sharp-tempered guardian can be a liability – in the legal sense as well as in general. This reality has shaped a shift in temperament in a large part of the breed, though the original character can still be found in stockdog ines.

An unconsciously selected benefit working/field strains may enjoy is better overall health. Dogs which cannot withstand a highly active physical regimen wash out early and are never considered for breeding, not because the breeders are necessarily health-conscious but because meeting their selection goals requires that their dogs remain in superb physical condition.

The divergence in show and working lines has also contributed to the loss of the full suite of working behaviors in a variety of breeds. This is not because show breeders deliberately select away from those behaviors, but because most are not making a conscious and consistent effort to maintain them. Complex traits cannot be maintained without consistent selection, generation after generation.

A final example of “thoughless” selection factors can be found in how some breeds dogs look. Considerable research has indicated that humans, and especially females, are attracted to babyish features in animals. Human nature, and perhaps the fact that the preponderance of people involved in dog breeding are female, has probably lead to the reduced size, larger eyes and shorter, blockier muzzles seen in several breeds today that did not exhibit these features a few decades past.

Ties that bind

Some traits go hand-in-hand, either because they are genetically linked, arising from genes that close together on the same chromosome, or biologically linked, with changes in one thing impacting the other. Not a great deal is known yet about genetic linkages for important breed traits, but examples of biological linkage between desired breed traits and undesirable things abound.

Many breed standards state that the dogs should have dark brown eyes, but in some of those breeds acceptable coat colors include brown (variously described as liver, chocolate or red) or dilute (as in blue or fawn Dobermans or any Weimeraner.) However, neither brown nor dilute dogs can have dark brown eyes. The pigment diluting effects of the genes involved (commonly referred to as “B” and “D” by dog breeders) also dilutes pigment in the eye, resulting in eyes that are light brown to amber in shade.

Recent study of the gene responsible for very small size in many breeds revealed that small dogs are genetically predisposed to excitability. So, if you want a small dog but don’t like dogs that are yappy or hyper, you may not be able to find what you are looking for, at least in those breeds whose smallness stems from that particular gene.

Selecting for body structures that vary considerably from the canine norm can also have unintended side effects. Some of these are well recognized and you can take steps to avoid them. Others you may not even be aware of. A recent study of short-faced breeds like Pugs and Boston terriers found that, because of their extremely short muzzles, the skull has altered to the point that their brains have rotated forward. As a consequence, the olfactory lobe, which process the dog’s ability to scent, has migrated to the lowest portion of their brains, probably to remain in reasonable proximity to the nose. At this time any effects this might have on these dogs’ behavior or sense to smell haven’t been determined.

While all of these secondary, environmental, and unconscious selection factors may not have a huge impact on any individual breeding, cumulatively they do influence the population genetics of a breed. By being aware of what these factors are and how they influence not only your decisions but those of other breeders you will be able to make more informed decisions for your own dogs.

Used with permission from Double Helix Network News.