Breeds & registries
Outcrossing
Bringing in unrelated animals — sometimes from another breed entirely — to widen a gene pool that has become too narrow to breed out of.
A closed studbook has a fixed amount of genetic variation and only ever loses some. When a breed's remaining population all descends from a handful of founders, selecting away from an inherited disease inside that pool stops working, because everything left is related to everything else.
Outcrossing is the way out, and it is contentious: it means accepting animals that are not purebred by the current definition in order to keep the breed viable. Several registries have run controlled outcross programmes, tracking the new line for generations before folding it back in.
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More in Breeds & registries
FCIThe international federation of national kennel clubs, which recognises breeds, sorts them into ten groups and lets each breed's country of origin write its standard.AKCThe main US registry, which keeps its own studbook, recognises a shorter list of breeds than the FCI and sorts them into seven groups.Breed standardThe written description a registry holds for a breed — proportions, coat, movement, temperament — and the document judges score against in the ring.MerleA coat pattern that dilutes patches of pigment into a mottled marbling — and a gene with real consequences when two merles are bred together.BrachycephalicShort-headed — a skull bred shorter front to back, producing the flat face of Pugs, French Bulldogs and Persians.PedigreeA registered record of an animal's ancestors — a family tree issued by a registry, not a guarantee of health or quality.