Registered purebred and percentage Kiko Goats raised for hardiness, meat and pack goat prospects
Kopf Canyon Ranch

What are Breeding Coefficients?

What is inbreeding, linebreeding
...and why do I need more than a pedigree to determine relatedness?

Breeders of purebred animals commonly employ one or more of the following breeding systems: inbreeding, linebreeding, and linecrossing. Each has advantages and disadvantages, and a breeder may wish to use only one system, or all three at different points to reach different goals.

Inbreeding: Defined as “mating together animals which are related so that the resulting offspring have one or more ancestors that occur on both the sire’s side and the dam’s side of the pedigree.” Close inbreeding would include the mating of full siblings, or father to daughter; more distant inbreeding might involve second cousins.

Inbreeding can lead to “inbreeding depression”, a reduction in vigor, fertility and disease resistance. Breeds and populations differ in their tolerance to inbreeding depression; a general guideline used by the American Livestock Breeds Conservancy (ALBC) is to keep inbreeding below 5% per generation, and 30% in any individual.

Linebreeding: A form of inbreeding, linebreeding involves concentration of a particular ancestor within a pedigree (rather than several ancestors, as in other forms of inbreeding). Usually, this individual is a particularly excellent representative of the breed. The goal is to create a flock as much like this individual as possible, so matings often involve breeding half-brother to half-sister.

Linecrossing: A line (or strain) is a group of animals that are more closely related to each other than to the population as a whole. They might be the product of an inbreeding or linebreeding program. Linecrossing is the mating of individuals from one such line to those of another line. Generally, linecross individuals will show greater vigor, better growth, and more ‘bloom’, or ‘presence’ than individuals from either of the parent lines for at least the first generation. Thus, linecross individuals are more likely to succeed in the showring. Linecrossing can also be used to bring new vigor into an inbred or linecross flock.