Estimated Breeding Values (EBVs)


  • Inbreeding occurs when a mating is made with a relative or the parents' shared common ancestors. The closer to the common ancestors by blood relationship, and the more common ancestors, the stronger the inbreeding.

  • The most severe inbreeding occurs in a sibling to sibling mating or offspring to their parents.

  • These matings occur in an effort to preserve features of a breed, or line within a breed, and is referred to as “line breeding”. The degree of inbreeding can be mathematically expressed as an inbreeding coefficient.
    • The inbreeding coefficient of an individual is defined as the probability that any two homologous alleles (same forms of the genetic locus) are identical by descent. That is, they were transferred from an ancestor to the current generation.

  • Inbreeding often occurs the deeper you trace a pedigree. It is impossible to avoid inbreeding in a small population, especially when the population has experienced a bottle neck.

  • Severe inbreeding could result in shorter lives and problems of fitness including hip dysplasia or cancer.   Levels of inbreeding in dogs registered in the OFA can be seen in this accompanying paper.  These levels are artificially low because we do not have pedigrees of all pure breed dogs born in the USA.