Inbreeding and Diversity – Part 5

Continued from PART 4

MORE ON INBREEDING

The dog world seems unwilling to learn from science in some respects, and inbreeding-linebreeding is one of those areas. I say “one” because there is no real difference or dividing line between the two terms; linebreeding is simply descriptive of inbreeding on animals a little further back in the pedigree than otherwise. Laboratory rats and mice have been consistently inbred to a great degree in order to be more predictive about the effects of medicines and other things that experimenters are working on. But such scientists keep several different families going at a time, because they know that restricting the gene pool also has adverse effects sooner or later, and when a line starts to die out because of inbred weaknesses, they can cross with another family or more, and start a new line again. In time, inbreeding results in “inbreeding depression”, with such signs as smaller size, less resistance to stress and disease, fewer offspring, and shorter lives. Doesn’t that sound awfully familiar to those of us who’ve been watching the American GSD develop over the past 40 or so years? Except for the smaller size, perhaps, but those wouldn’t reach the mainstream of the market anyway. We dog breeders do not have the ability as individuals or associations to maintain dozens of separate bloodlines as the lab mice breeders do.

The more research into inbreeding and genetic diversity is carried out, the more evidence mounts that artificial selection is deleterious and natural selection results in a much broader diversity and therefore greater health safety level. Even in Germany, where breeders formerly prided themselves on keeping “open” at least important sire lines that went back to dogs not found as often in modern pedigrees, it has become almost impossible to find GSD “show” dogs that are not linebred on Palme WildsteigerLand and the Q-litter Arminius. As a result of moderately strong linebreeding, we find such problems as the immune system deficiencies in Lasso Neuenberg and others’ offspring, nagging high levels of HD in Zamb Wienerau descendants, low percentages of Körklasse-1 (or even Kkl-2 for that matter) in Tacko Wienerau and even some offspring of Siegers. These are not prejudicially singled out; they are too representative of many, many dogs in the same boat. When “everybody” breeds to the same small number of dogs or bloodlines, these types of weaknesses are what you’ll get.

The loss of diversity of genes is directly responsible for much of the genetic problems we see in many species of domesticated animals, not only dogs. Some breeds of swine, for example, almost have to be slaughtered by the age of 5-7 months to take advantage of the best ratio of sale price to feed cost, but also to avoid the almost inevitable hip dysplasia in those breeds. Only a few of the better-hip pigs or those on a less accelerated diet are kept long enough to breed from. If the Germans don’t start tightening up on GSD hip and elbow joint quality, and loosening up on the narrow focus of the bloodlines used (working lines are almost as bad in this respect as show lines), they will soon paint themselves into a corner the way the Americans have. Inbreeding depression walks hand-in-hand with loss of heterozygosity and the lower utilitarian beauty of the modern German Shepherd Dog.

The name “Border Collie” in the U.S. and a few other countries, was until recently in the same position the GSD was a hundred years ago, more a description of its occupation than its ancestry. Thanks to the self-serving and wrong-headed approach of the AKC, the Border Collie has become a “breed”, with all the dubious rights and appurtenances thereto granted by the AKC, including severe restriction of genetic diversity. This true working breed is beginning to find itself in the same position the Akita has been in for all those years the AKC refused to open the stud book to imports from the country of origin. The Akita has a host of health and temperament problems as a result. New “rare” breed clubs have formed in the U.S., partly to satisfy the desire for novelty, partly as a haven for those fleeing the more established breeds after disappointments in genetic health. But that’s jumping from the frying pan into the fire.

The “Shiloh Shepherd”, a new breed (30+ years in the making so far) is basically a GSD family chosen for large size, old-fashioned level-back stance, and allowable profuse long coats. To bring in the desired qualities that the founder couldn’t find enough of in the regular GSD, fanciers reportedly have brought in a couple other breeds in very small quantities. Still, the gene pool is extremely limited, and unless there is use of strict selection techniques for eliminating HD, dentition faults, and a few other problems, the breed will continue to have all the traditional inbred-GSD disorders plus a few more. The white GSD, recognized by some registries as a separate “breed”, the White Shepherd, White Herder, and other names, likewise has a host of structural and other limitations and is at risk of genetic disease taking it over because of its lack of genetic diversity. The Chinook, based on a single big yellow dog of mixed Saint Bernard and other heritage, is being modeled into a more or less consistent Type by the “national” club via the use of “imported” genes from Siberians, Shepherds, and whatever results in the desired body style and personality characteristics. The English Shepherd is being pulled in two directions by those who want to breed for style and show in conformation, and those who want to leave it as it is (currently a tremendous variation in appearance from an Australian Shepherd to Border Collie to almost a Leonberger look); the latter stress its farm and pet utility instead of pedigree. Whether “new” or not, breeds on the edges of what some consider “purebred” are faced with the challenge to keep enough diversity to prevent problems from becoming so deeply imbedded in the gene pool that there is almost no correction possible.

Today, almost all black Poodles (and their genetic diseases) are bred on the Wycliffe line. Poodles are numerically among the worst afflicted with epilepsy. Dalmatians have a sack full of genetic disorders, and when the AKC and others proposed a scheme to rid the breed of hereditary deafness by judiciously blending a few Pointers into the breed, then culling to preserve Dal type while eliminating carriers, the Dalmatian club rebelled against logic and voted to stay on the course to self-destruction. Many feel that the Siberian Husky is a genetic mess because of the restriction to breeding only “pure” ancestry; they can’t work as well as sled dogs as can the mixed breeds which constitute the “Alaskan Husky”. Some 80% of Doberman Pinschers are either affected by, or carriers of, the genes for von Willebrand’s Disease (vWD), which means that those fanciers are in a real bind, as elimination of all those dogs would mean disaster for the breed. Copper toxicosis in the Bedlington; elbow dysplasia in the Rottie; PRA in the Irish Setter and Lab; PFK enzyme deficiency in American Cockers, English Springers, and Basenjis; dwarfs and hemophiliacs in the German Shepherd Dog, and many other examples of genetic disease are linked to the decrease in outcrossing over time. Germans for the most part still echo the official (but untrue) line that Canto was not a Type-A hemophiliac, and for a long time many of his GSD descendants suffered from that disorder; fortunately it is sex-linked so that only daughters are carriers of the recessive and sons tend to die early, and it has not been seen in recent years to be a major problem.

Whenever possible, outcross! And encourage the national breed club to use genetic diversity in recognizing the value of the dogs and lines. To quote an Internet/e-mail message on the subject, we all should take a closer look at “the dark side of inbreeding — what happens when everyone breeds to Mr. Wonderful, and what to do when everyone discovers they have the same problem.” (Genetic Diversity Project, Dr. Catherine Marley and Dr. John Armstrong). University of California-Berkeley canine genome researcher Jasper Rine sums it up: “There are just crazy levels of inbreeding in many breeds of dogs”.

One common route to inbreeding is the widespread use of a single popular “Grand Victor” or “Sieger” (national top winners), or a handful of top Award-of-Merit/Select animals to the exclusion of other good but less-highly placed competition dogs. While you may be increasing the chances of getting a dog that has some of the same obvious (probably dominant or homozygous) desirable qualities, you are at the same time increasing the concentration of so far hidden recessives, many or most of which are bad for the breed. When most people flock to the leaders for stud service, these bad genes are concentrated as well, and the good genes that an unused dog could have contributed may be lost forever. The undesirable recessives previously hidden in the lines will soon become glaring problems, impossible to ignore and difficult to get rid of.

END

Fred Lanting

Fred Lanting is an internationally respected show judge, approved by many registries as an all-breed judge, has judged numerous countries’ Sieger Shows and Landesgruppen events, and has many years experience as one of only two SV breed judges in the US. He presents seminars and consults worldwide on such topics as Gait-&-Structure, HD and Other Orthopedic Disorders, and The GSD. He conducts annual non-profit sightseeing tours of Europe, centered on the Sieger Show (biggest breed show in the world) and BSP.

Books by Fred Lanting