At its best, breeding is a blend of science and art. The skilled breeder has at least general knowledge of genetics and health, and in-depth knowledge of the breed standard and conformation points of his chosen breed. Most breeders are fiercely loyal to their dogs, and are concerned about each individual animal.

At worst, breeding can be a slipshod enterprise in which the major concern is profit, with little regard to the health and welfare of the dogs involved. These often take the form of so-called ‘backyard breeders’ (the term for random or ignorant breeding conducted on a small scale), and ‘puppy mills’ or ‘puppy farms’ (larger businesses). It must be pointed out, however, that many excellent breeders run small-scale programs in their homes, barns, or back yards, and there are profitable large-scale operations run with knowledgeable staff and superlative veterinary care, so size and motive alone are not indicative of the quality of the breeding program.

The birth of a litter of purebred puppies is recorded on a breed registry maintained by an all-breed kennel club or a breed club. Such registries are not the exclusive province of show dogs, as is sometimes thought; the clubs of working dogs also maintain records of their dogs’ lineage.

A responsible breeder checks each puppy for health and conformation

Requirements for the breeding of registered purebreds vary from club to club. Most breed clubs allow for any registered puppy to be bred from once it reaches a suitable age. Some clubs maintain an adjunct or limited register, for puppies of purebred parents not deemed to have the qualities for showing or breeding, or who exhibit a fault. A few clubs, such as the Swiss breed club of the Greater Swiss Mountain Dog, the Jack Russell Terrier Club of America and the Mini Foxie Club of Australia, Inc. have additional, strict requirements for the certification of adult dogs before breeding.

See also

• Selective breeding