Whitney Price <[EMAIL PROTECTED]> wrote
>I would find it quite enlightening to hear the possible effects of
>inbreeding. I have a second-generation pair and know I'll need to pull in
>new DNA after this generation, but I'd like to know what happens to gerbils
>if inbred.
Normally, nothing. All inbreeding does is to bring together genes in
combinations that otherwise would be very uncommon by reducing the pool
of available genes and then continually recycling them.
This can be a good thing. The reason the pedigrees of horses and dogs
are controlled is because a small gene pool which creates desirable
characteristics has been obtained and control is needed to make sure the
pool does not get smaller, and that less desirable genes are introduced.
Horses are a good example of how a limited gene pool and inbreeding can
be used to produce "better" animals.
The problem is that a small gene pool may bring together undesirable
characteristics. These could be almost anything. They could be a
propensity to fit, missing toes, deformed ears, increased incidence of
tumours, vulnerability to certain illnesses, reduced fertility etc.
The only things I have seen that are probably caused by inbreeding are:
Tumours, abnormal wrist joints and inner ear problems. A responsible
breeder will avoid inbreeding unless there is a good reason to do so for
a small number of generations and will avoid any breeding that tends to
result in abnormalities. So, for example, if it became apparent that
gerbils descended from a particular pair were more likely to die early,
for example, you should track down all the descendants of that pair and
stop breeding from them.
All good books on dog, cat, horse, or agricultural animal breeding will
have sections on inbreeding, "fixing" characteristics, identifying
defects and avoiding them.
--
Julian
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* Jackie and Julian *
* [EMAIL PROTECTED] *
* National Gerbil Society *
* http://www.gerbils.co.uk/ *
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