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 is a measurement, not a verdict
The coefficient of inbreeding estimates the probability that two copies of a gene in an animal are identical because they come from a shared ancestor. A higher figure means more shared ancestry between the sire and dam, and generally more risk, but it is only one factor to weigh, not a straight pass or fail test.
The figure only makes sense against a benchmark
A COI that would be alarming in one breed could be unremarkable in another with a naturally smaller founding population. Comparing a pairing's COI against that breed's typical range is more useful than looking at the raw percentage alone.
What COI percentage is considered safe?
There is no single benchmark that applies to every breed. Many breeders aim to stay below their breed's average, which can differ significantly from breed to breed.
How is COI calculated?
COI is calculated from a pedigree, tracing shared ancestors across generations. Most breed registries and several online tools can calculate it once a pedigree is submitted.