What do the tests really mean?
It's important to assess the available testing for our breed realistically and not like we accept testing because others will peck us like the weak chickens if we don't conform to their standards. Some standards are meaningful and some aren't, but which and why? Our intellects should govern our actions more than peer pressure.
- Is a test definitive? Can the results be different if taken tomorrow?
- What is the mode of inheritance for a disease?
- Do we understand the difference between autosomal recessive and dominant genes?
- Do we understand what a complex or multifactorial inheritance is?
- Do we understand incomplete or reduced penetrance of expression?
- Do the researchers working on this disease know what the inheritance is, or are they guessing, and how reliable is their proof?
- How much influence may environment play in the expression of a disease, either specifically in an individual, or epigenetically?
- What kind of risk is there for the disease for each dog? And what quality of life can be expected?
Decades ago, a terrifying amount of diversity was lost because the crowd decided a "good breeder" was one that prized aesthetic type over other traits.Now the same is true with testing criterion. Many a less than perfect looking dog was removed from the gene pool, and now many with imperfect health testing or imperfect relatives have been eliminated as well. Likewise, some dogs with desireable type and acceptable testing (much of which does not predict future health) have had too much influence on the population because they were repeatedly bred despite their bad temperaments or mediocre health, or unreliable "clear" health tests that were never predictors of future health.
To assess our options, we went through the tests that have statistics on the Orthopedic Foundation for Animals, OFA, since these are perhaps the most reliable long term statistics available. We checked with the OFA to be sure the aggregate statistics include those that owners choose not to publicize and they do. Next...