Pedigree (dog)

A purebred dog typically refers to a dog of a modern dog breed with a documented pedigree in a stud book and may be registered with a breed club that may also be part of a national kennel club.

Purebred dog may also be used in a different manner to refer to dogs of specific dog types and landraces that are not modern breeds. An example is cited by biologist Raymond Coppinger, of an Italian shepherd who keeps only the white puppies from his sheep guardian dog's litters, and culls the rest, because he defines the white ones as purebred. Coppinger says, "The shepherd's definition of pure is not wrong, it is simply different from mine." However, the usual definition is the one that involves modern breeds.

The earliest use of the term "pureblood" in English referring to animal breeding, according to the Online Etymological Dictionary, was in 1882 and "pure bred" in 1890. The Merriam-Webster Online Dictionary dates the use to 1852.

Purebred dogs are pedigreed members of modern breeds. These dogs may be registered with breed club. The breed clubs may be an open stud book or a closed stud book, the term can be interpreted to either. Usually the breed club is also associated with a kennel club (AKC, UKC, CKC etc.). However dogs who are registered with a breed club are usually referred to as "registered". Some use the term exclusively for a dog that has also been registered with a breed club, but more often it is used simply as a generic term to refer to dogs who have known pedigrees within a standardized breed. A dog that is purebred cannot be interpreted to mean it is high-quality dog. It is no reflection on the quality of the dog's health, temperament or sagacity, but merely a reference that the dog has known parentage according to the breeder. While some breed clubs can now guarantee parentage through DNA testing for the most part all breed clubs must rely exclusively on the breeder's word and choice of parentage. In the early years of the kennel club concept this was not at issue since dog breeding was only done among the extremely wealthy and their reputations were at stake. However in this modern age of breeding one must be aware that even a DNA proven purebred and registered champion who has won national competitions can have serious health issues.

Dog crossbreeds (first generation crosses from two purebred dogs, also called dog hybrids) are not breeds and are not considered purebred, although crossbreds from the same two breeds of purebreds can have "identical qualities", similar to what would be expected from breeding two purebreds, but with more genetic variation. However, crossbreds do not breed true (meaning that progeny will show consistent, replicable and predictable characteristics), and can only be reproduced by returning to the original two purebred breeds.

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Wikipedia