The New York Times reports that testing of racing whippets has revealed the causal agent for "bully-whippets" which are so morphologically different than their dams and sires. It seems that by crossing the fastest whippet with the fastest whippet, a breeder can "double down" on a defective myostatin gene. A single copy of this gene makes for the fastest whippets at the track or in the field, while a double dose of the gene (a full pair) and you get a heavy-bodied and thick-headed dog that looks like a very ugly labrador cross.
For more on the limits of breeding "the best to the best" -- and why that is no longer done ad infinitum with cattle, see >> Inbred Thinking
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I was completely dismayed when AKC recognized Border Collies, and real glad the herding registries remained discrete from what they will inevitably do to the breed. We have three BCs from working stock that look nothing like one another. They work though and that is what we need from them.
ReplyDeleteDairy cattle are faced with similar inbreeding problems, although many farmers are now crossbreeding to obtain hybrid vigor. They at least recognize the inbreeding problem among purebreds. Bull proofs, which compare the offspring of various bulls, penalize those most inbred. Thus a bull may produce daughters that give a great deal of milk but if he is significantly inbred this will lower his proof. It may be too little, too late, but at least the effort is being made.
Um, I'll take the whippet on the left.
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