"The ultimate long-term goal for everyone is that if we come up with a panel of risk factors, then we'll be able to put together
a risk assessment to apply to an individual animal," says McCoy. This will help identify an individual animal as having an
increased or decreased genetic risk of disease.
"If we can identify those horses with a high genetic predisposition to osteochondrosis, then we might be able to intervene
early with changes to some of the management, nutrition or exercise factors that we know are important, and we may be able
to help prevent disease development," says McCoy.
For high-risk horses, researchers could then start checking early for development of disease so veterinarians can make a decision
about conservative management or surgical intervention at a young age, before pathology develops. The biggest risk for osteochondrosis
is that, if it is left untreated, young affected horses can develop arthritis in a joint. Knowing which horses may be affected
also can impact breeding decisions. Of note, horses treated early often go on to perform very well, so breeders may be reluctant
to remove affected individuals from a breeding program.
"We'll have to deal with some of those decisions down the road, realizing this is a polygenic disease and there are a lot
of genes involved, which complicates matters," says McCoy, "Certainly, if you know the stallion and mare both come from a
high-risk line, maybe that's not a breeding you would choose to make. It's going to be one more a tool for breeders and veterinarians."
Ed Kane, PhD, is a researcher and consultant in animal nutrition. He is an author and editor on nutrition, physiology and
veterinary medicine with a background in horses, pets and livestock. Kane is based in Seattle.
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