A breed of dog is produced by selecting and mating dogs with certain desired characteristics. The offspring of such matings are then inbred, i.e., mated with litter mates or close relatives. After about eight generations, the line usually breeds true, i.e., most offspring resemble each other. Then standard traits can be established for the new breed. A purebred dog is one that conforms to the standards of a certain breed and whose lineage, or pedigree, has been recorded for a certain period of time.
One of the principal functions of a kennel club is to maintain the records of lineage of individual purebred dogs in order to preserve breed standards. The stud books of the AKC contain entries for all purebred dogs whose owners have elected to register their dog's pedigree. Other stud books, such as those of the United Kennel Club, often record dogs of breeds not recognized by the AKC but which have a considerable following in the United States. Dogs of mixed origin or whose parentage is unknown are called mongrels.
Attempts to classify dogs probably date from the time when humans discovered that certain canine traits were more useful than others. The earliest known system of classification, that of the Romans, included categories for house dogs, shepherd dogs, sporting dogs, war dogs, dogs that ran by scent, and dogs that ran by sight. Today there are systems of classification and breeding in most countries of Western Europe and in North America, many using a variation of the standard British system.
In the United States, the classification system most frequently encountered is that employed by the American Kennel Club (AKC), which recognizes more than 150 of the more than 200 known breeds. The breeds are grouped into six classes. In the sporting dog group are pointers, retrievers, setters, and spaniels. These dogs hunt by air scent as opposed to those of the hound group, e.g., beagles, foxhounds, and bloodhounds, which track their prey by ground scent. Also classified as hounds are those dogs of the greyhound type, e.g., whippets, borzois, and Salukis, which hunt mainly by sight. The many breeds of terrier go to earth after their burrowing prey. Among the working dog group, used as guards, guides, and herders, are the collie, the German shepherd, and the St. Bernard. Such diminutive pet dogs as the Pekingese, the Pomeranian, and the pug belong to the toy dog class. The nonsporting dog group is a class of dogs bred principally as pets and companions and includes the Boston terrier, the bulldog, the chow chow, the Dalmatian, and the poodle. In addition to the breeds in the above classes, the AKC currently places additional breeds in a miscellaneous group; breeds recently recognized by the club are placed in this class until they become established. Included are the Akita of Japan, the Australian cattle dog, the Australian kelpie, the Bichon Frise (a French descendant of the water spaniel), the border collie (an English shepherd dog), the cavalier King Charles spaniel, the Ibizan hound (of Spanish origin), the miniature bull terrier, the soft-coated wheaten terrier (from Ireland), the Spinone Italiano, and the Tibetan terrier.
Dogs registered by the AKC and other registry associations compete regularly in dog shows and field trials. In dog shows, the various breeds are judged solely on appearance, while in field trials they are rated according to their hunting skills.
See articles on individual dog breeds.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.