Why low inbreeding isn't always the priority in purebred dog breeding
A look at why purebred dog breeding doesn't always prioritize low inbreeding coefficients, what pulls against it, and how pedigree data and genetic testing can shift that balance.
Inbreeding & COI
COI measures risk, it doesn't hand out a verdict
The coefficient of inbreeding estimates the chance that two copies of a gene in an animal are identical because they descend from the same ancestor. A higher figure signals more shared ancestry between the sire and dam, and generally more risk, though it remains one factor among many rather than a simple pass or fail test.
A number on its own tells you very little
A COI that would raise eyebrows in one breed might be entirely ordinary in another that grew from a smaller founding population. Checking a mating's COI against that breed's usual range matters more than reading the raw percentage in isolation.
Is there a safe COI percentage?
There's no fixed threshold that applies to every breed. Most breeders try to keep below their own breed's average, and that average can vary a great deal between breeds.
How is COI figured out?
It's worked out from a pedigree by tracing shared ancestors over several generations. Most breed registries, along with a number of online tools, can calculate it from a submitted pedigree.