> Could you please tell me what gene pool dilemma the Club is having. I wasn't > aware of one. And besides you can't improve the gene pool that was set in > stone by the I think 8 dogs that the breed was started with. I do all the > testing and haven't run out of older heart clear dogs to breed to yet.
This is precisely what I mean by misconceptions. You are basing your opinion on one statement made by one geneticist--an opinion which is not quite the true issue we need to address. All you need to do is go to your search engine and start searching on genetic diversity and gene pools in dogs. You will find oodles of articles that point this out. If you look long and hard, you might, with luck, find one or two articles that sort of support what this geneticist said. But not really. I think you might find out he was talking apples and we need to talk oranges. The gene pool all by itself is not technically the issue. What is the issue is what genetic makeup does each dog have inside that gene pool. Let's breed two dogs together. We will breed Ch. A to Ch. B and produce a litter. Does each puppy in that litter have the same genetic makeup? Or is each different? Is the genetic makeup of any puppy in that litter identical to any other dog on earth? We all know the answer--each is different unless they happen to come from the same egg and sperm. So every single dog in a gene pool has a different genetic makeup save those identical twins, triplets, etc. This is what creates genetic diversity. If every Cavalier that is used in a breeding program in the U.S. has a different genetic makeup--how can you say that the gene pool is set in stone? There are also mutations happening so the gene pool is never static. It is always changing. Definitely NOT set in stone! What really matters is that genetic makeup and what the inbreeding coefficient is of the particular dogs. As the Dog World article states: *The secret to health and viability of wild animals is permanent severe selection plus high genetic diversity.* When we breed purebred dogs we are decreasing genetic diversity, going against nature. Restrictive breeding practices such as what has been placed on CKCSC and AKC-only Cavaliers decrease genetic diversity even more and therefore are deleterious to the health and welfare of Cavaliers. It is well known that high inbreeding coefficients are deleterious to good health and longevity. In most species an inbreeding coefficient above 9% will have negative health effects. Dogs with inbreeding coefficients of 6% live, on average, 4 years long than dogs with inbreeding coefficients of more than 25%. Here is an extreme example of why: We will assume in breed X, 5 percent of the population are nonaffected carriers of a gene for disease *Y*. If a brother/sister mating occurs between two of these carriers, with totally unrelated ancestors, the coefficient of inbreeding will be 25%. This means the resulting puppies will have lost a fourth of the original genetic diversity of their parents and are at 8.6 times greater risk for disease Y than non-inbred dogs. Although the way most of us breed purebred dogs is not that extreme, it is well known that the more you restrict genetic diversity (as is happening in our breed) the greater the damage that is done to the health and welfare of any particular breed. The biggest risk from loss of genetic diversity is a reduction in immune system capability. Yes they do have dramatically inbred rats that seem *healthy*, but only in a laboratory. Their immune system function is so reduced that they are not capable of living in the outside world. Genetic diversity is essential to good immune system function. The question is if we even have enough genetic diversity in any particular breed to keep on breeding them in their pure state without further loss of vigor. This is being discussed at the AKC Canine Health Foundation already. They are pretty sure that loss of genetic diversity has contributed to the health problems that are increasing in frequency and severity and will continue to do so in the future. They are trying to figure out what to do about this. Every breed needs as much genetic diversity as it can get if it is to survive. And yet CKCSC places even further restrictions on genetic diversity in our breed by refusing to allow AKC-only dogs to be used. I consider this deleterious to the health and wefare of the Cavalier! Laura Lang ========================================================= "Magic Commands": to stop receiving mail for awhile, click here and send the email: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20NOMAIL to start it up gain click here: mailto:[EMAIL PROTECTED]?body=SET%20CKCS-L%20MAIL E-mail [EMAIL PROTECTED] for assistance. Search the Archives... http://apple.ease.lsoft.com/archives/ckcs-l.html All e-mail sent through CKCS-L is Copyright 2002 by its original author.
