Genetics is one of my favorite topcis to teach in my college
bio classes and I often use canine examples. A large gene pool is
theoretically great but is only useful if all members are participating in
breeding. It is true that if all members of a *species* are
interbreeding recessive diseases and health issues are much more rare.
Please remember that in the case of a dog breed we are automatically dealing
with an artifically-selected subset of the species so the gene pool is
already reduced and modified.
In the case of show-quality dogs the gene pool is further
reduced. Certain individuals and lines are used much more extensively
and it's the care a breeder takes to *not* breed dogs with defects
that matters. But we all know that there are breeders who breed
dogs that have known defects because the value of other
characteristics of the dog prevail. So we have to think about the
actual gene pool that is being used - just because a breed becomes popular
and more numerous doesn't solve any problems. This leads to the second
issue, as we all know - back-yard breeders, often well-intentioned
people who are just naive, that breed without checking for known disorders in
the breed. They usually don't know what the issues are and certainly
wouldn't pay the hundreds of dollars to have their dogs checked prior to breeding
- even if they think they are going to make lots of
money selling pups. There is no quality-checking going
on. In both cases (unethical breeder and back-yard breeder) the
appearance of recessive genetic/health problems is not being addressed through
good selection of the parents of the next generation. (Please realize I do
know that sometimes these issues arise after a dog has been bred, sometimes
extensively - but it's still the breeder's duty to make every effort to get
that genetic set out of the breeding pool.)
Speaking to the choir here, I'm sure, but really, the only
way to clear up these problems is for breeders to be responsible in their own
crosses and for breeders to be sure pet-quality puppies they sell
are spayed or neutered. Even the sale of show-quality puppies should
include some assurance that the new owners have knowledge of possible
genetic/health issues and must return to the original breeder before
breeding their dog.
Personally I see trends in breeds that don't seem to make
the breed more "popular" to the general public - such as the newer
type German Shepard that crouches in the rear end and the changes in the
Irish Setter prior to that. Somehow the breeds morph into new
"trendy" forms and I'm not sure how that occurs - I certianly don't
think it's a preference coming from the general public - except perhaps by
the overdue influence of certain breeders?
Laurie
--- On Thu, 12/10/09, Amy Bailey <amy.bailey@myfairpoint.net>
wrote:
From: Amy Bailey <amy.bailey@myfairpoint.net>
Subject: RE: [pyrnet] RE: Pedigree Dogs Exposed
To: pyrnet-l@pyrnet.org
Date: Thursday, December 10, 2009, 11:00 AM
Makes
sense that popular dogs will be healthier if there is a large gene pool
to start. They stated that the Cavalier is the sixth most common dog in
the UK. Could be that too few were used to start to breed, so many are
now inter-related. I agree that irresponsible breeders are
to blame, but they are responding to a market so popularity does matter.
If people were not interested in the dogs, there would be no reason to breed
more. It may be very difficult to remedy the situation for this
breed in the UK now without importing different lines. According to
this report, serious heart and neurological issues are now common to the
breed in the UK.
Amy
From:
owner-pyrnet-l@pyrnet.org [mailto:owner-pyrnet-l@pyrnet.org] On Behalf Of KEITH
WEBER
Sent: Thursday, December 10, 2009 10:40 AM
To: Pyr-Net
Subject: [pyrnet] RE: Pedigree Dogs Exposed
Hello,
I do not think popularity really has anything to do with the health of
the breed. If you really think about it, the very popular breeds... ones with
millions of dogs, should be the most healthy (phyically and genetically)
as there will be a large gene pool and lots of good sires/dams to select
among and pair up.
The real problem underlying the health issues is irresponsible
breeders. The ones who are in it to produce a product
(puppies) and make money. Of course, these folks are not breed
fanciers of any sort, they choose a marketable breed, get a
male and female, and start up the assembly line.
I am quite disgusted with these sorts of folks... they are going to ruin
lots of breeds.
Keith and Soo
Weber
http://www.sdk-weber.com
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