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Purebred Dog Breeds into the Twenty-First Century:
Achieving Genetic Health for Our Dogs
Dr. Jeffrey Bragg
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An Example from One Breed
Thus the recognition of a breed creates a founder event when the registry is opened; a limited number of breed foundation animals are selected, often from a population which has already undergone considerable inbreeding and selection. Let us take for an example the Siberian Husky breed. Registered in 1939, the initial CKC population consisted of 47 animals, all belonging to or bred by one kennel! Of those 47, nine were foundation stock of the kennel whose dogs were registered. Two of those were males imported from Siberia - littermate brothers! The other seven were mostly related to one another. (Two were seven-eighths Siberian and one-eighth Malamute.)
The other thirty-eight were all progeny and grand-progeny of the founders. Of the nine foundation animals, two were not bred from at all. Two were mated - once only - to each other: one only of their progeny contributed to further breeding. Of the two Siberia import males, one brother was always bred to the same bitch, producing a large number of progeny of identical pedigree; the other brother was usually bred to daughters of the first brother. Today Siberian Husky lines that trace directly back to the Canadian foundation stock owe 25% of their pedigree lines to the first brother, 15% to the second brother, and 27% to the first brother's invariable mate! Two-thirds of the genetic heritage of these modern Siberian Huskies derives from only three foundation animals! This is not an exceptional situation, it is a fair example of the early breeding history of CKC breeds.

In the case of the Siberian Husky, then, (which happens to be my breed, with whose early history I am reasonably well familiar), The Canadian Kennel Club opened a registry in 1939, inspected one kennel's dogs and admitted four dozen closely-related individuals to the registry, which was then closed permanently. No effort was made to ensure a broad foundation, nor a numerous one, nor a genetically diverse one.

Just how permanently the registry was closed I recently found out when I imported from Russia a dog bred to the Siberian Husky standard! The dog was born in the Ural Mountains well within the boundaries of Siberia from parents of Chukotkan village origins; he had three generations of known ancestry (without registration numbers since there is no official "Siberian Husky" registry in Russia). I was immediately told that the Club "did not know what to do" about my application to register the dog, that the protocols used to register breed foundation animals in 1939 were no longer valid, and that my dog "should not be used for breeding because it would probably be a long process," in spite of the fact that the dog had a valid FCI Export Pedigree from the Czech Republic (through which he was exported). A year and a half later after repeated in camera discussions, the import was refused recognition by the Board and Registration Committee on grounds of inadequate information (no ancestral registration numbers). Repeated calls for Club inspection of the import and offers to submit the animal to DNA tests and progeny testing were ignored. The registry is closed - even to new Siberia imports!

For the past fifty-six years, then, all Siberian Huskies bred in Canada have stemmed from the 1939 registrations, or from American imports, which mostly stem from the same dogs CKC registered, plus perhaps three additional animals. The original foundation animals were poorly utilised and subsequent generations were so closely inbred that the two Siberia import males plus one bitch are even today still statistically equivalent to grandparents of every single Siberian now registered!
Thus the original founder event in my breed plus the closed studbook has resulted in a state of forced inbreeding for Siberian Huskies. There is no such thing as an outcross mating in Siberians in any genetically meaningful sense. A sire can be found, perhaps, who may have no ancestors in common with a bitch for the last 5 or 6 generations - if one knows all Siberian bloodlines well enough and doesn't mind going a few thousand miles to find him - but he will not be an outcross, because all of his ancestors and all of the bitch's ancestors are the same animals, once the pedigree is taken back far enough. It would be difficult to calculate inbreeding coefficients for fifteen to thirty generations of ancestry; software to handle calculations of that nature doesn't seem to be generally available to breeders. (After all, a thirty-generation pedigree would contain over two billion names.)

Thirty generations of breeding all going back to ten dogs or fewer represents an impressive feat of sustained inbreeding! Predictably enough Siberian Huskies, which eighty-five years ago were probably the toughest, hardiest variety of dogs on earth, now suffer from the same gamut of genetic defects that afflicts other breeds. Few if any registered Siberians are now able to perform as sleddogs on anything approaching the level of the 1910 dogs imported from Siberia. Probably this is mostly due to the decline in heterozygosity and loss of vitality through inbreeding. What is worse, unmistakable signs of inbreeding depression are surfacing in the breed: rising numbers of Caesarean births, smaller litters, lower birth weights, delicate nestlings prone to infection, etc. Breeders of domestic livestock - cattle, poultry, sheep - manage to run registries and maintain breed type without imposing the concept of absolute breed purity. They inbreed to fix desirable traits, as do dog breeders. Livestock breeders, however, do not try to pretend that they can inbreed forever without ill effects. Thus when inbreeding depression or genetic defects threaten, they outcross - repeatedly, if necessary. They can do so because they do not have closed studbooks. I do not suggest that we slavishly copy the procedures and registry structures of livestock associations, because I think they, too, might benefit from some restructuring in the light of modern genetic knowledge.
Nonetheless I would make the point that we in the canine fancy are in a minority when we cling to absolute ideals of breed purity and insist on rigidly closed studbooks.
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© Jeffrey Bragg, 1996
P.O. Box 4124, Whitehorse, Yukon Territory, Canada YlA 3S9
Scanned into electronic form by Jolanta Jeanneney. Initial formatting and editing by Martin Vuille. HTML formatting by John Armstrong (jbarm@uottawa.ca).