Re: [pyrnet] Pyr eyes

[darrell goolsbee <dgg@star-telegram.com>]

<<How do you ever get to the 25% or less if you never use any offspring
> of a known dog carrier or affected?>>

I would assume he is talking about looking back at a dog's pedigree,
rather than breeding down to achieve that goal. Dr. Aguirre is one of,
if not the premier, expert(s) on PRA, and his recommendation is not to
use a dog that is the offspring of a known carrier or affected.

Breeders can take that advice or not, but remember that PRA is a VERY
serious disease, much more serious than dwarfism, for example. From my
talks with some breeders I know, I am guessing that there may be some
confusion because many Pyr breeders are used to dealing with dwarfism as
a model on what to do and what not to do when breeding recessives.
Because the affecteds in dwarfs are usually obvious and the
non-affecteds are healthy, breeders may well be willing to take some
risks in dwarfism that would not be considered good breeding practice
when dealing with a very serious disease like PRA, which is a blinding
disease. Dealing with PRA, juvenile cataracts and SAS (which is likely
not a simple recessive) may require a different and more aggressive
mind-set if the breed is to be spared great damage.

When doing research on SAS, for example, I talked to the Newf HC
chairwoman, and she recommended that we act very aggressively to curtail
the disease before we have rampant problems. Are Pyr breeders willing to
do that? I think that is very much an open question. 

<<Also in order to even identify the
> affected
> dogs, much less the carriers you have to extensively test.>>

Which is what the PRA-affected breeds do, relentlessly. I don't know
that we are to that point yet, but we may need to start thinking about
it.

Darrell Goolsbee
Fort Worth, TX