List of guinea pig breeds

Guinea pigs, also known as cavies (Cavia porcellus), have been domesticated since around 5000 BCE, leading to the development of a diverse array of breeds. These breeds exhibit a wide range of physical characteristics and serve various purposes. Some are show breeds, notable for their long, flowing hair, while others are laboratory breeds, used as model organisms in scientific research. The period from 1200 to 1532 CE, which coincides with the Spanish conquest of the Inca Empire, saw indigenous South Americans selectively breeding guinea pigs. This resulted in numerous landrace varieties of domestic guinea pigs, which have since become the foundation for some of the formal modern breeds.^[1] Early Andean varieties were primarily kept as agricultural stock for food, and efforts at improving cavy breeds (cuy) bred for food continue to the modern era, with entirely separate breeds that focus on size and disease resistance.

With the export of guinea pigs to Europe in the 15th century, the goal in breeding shifted to focus on the development of appealing pets. To this end, various competitive breeding organizations were founded by fanciers. The American Cavy Breeders Association, an adjunct to the American Rabbit Breeders Association, is the governing body in the United States and Canada.^[2][3] The British Cavy Council governs cavy clubs in the United Kingdom.^[4] For Australia and New Zealand, there are the Australian National Cavy Council and the New Zealand Cavy Council.^[5][6] Each club publishes its own "standard of perfection" and determines which breeds are eligible for showing. New breeds are continuously emerging, which may or may not be recognized by these breeding organizations.

Though there are many breeds of guinea pig, only a few found on the show table are common as pets. Most pet guinea pigs were either found undesirable by breeders,^{[clarification needed]} or else were bred to be pleasant pets regardless of how well they met the "standard of perfection" for the breed. The American (short-haired), the Abyssinian (rough-coated), the Peruvian (long-coated), and the Sheltie/Silkie (also long-coated) are the breeds most frequently seen as pets. Besides the Silkie, they also historically form the core breeds in the competitive showing of guinea pigs. In addition to their standard form, nearly all breeds come in a satin variant. Satins, due to their hollow hair shafts, possess coats of a special gloss and shine. However, there is growing evidence that the genes responsible for the satin coat can also cause severe bone problems, including osteodystrophy and Paget's disease.^[7] For this reason, some cavy breeders' associations, namely the Nordic ones, prohibit showing satin variations because of animal welfare concerns.

All cavy breeds have some shared general standards: the head profile should be rounded and have large eyes and large, smooth ears; the body should be strong and of compact build; coat color should, in all variations, be clearly defined and thorough from root to tip. These standards are best met by long-established, commonly bred breeds, as their breeders have had enough time and animals to effectively breed for these qualities. The coat color ideal—good definition and thoroughness—is rarely met by breeds other than the smooth-coated ones, which have had well-established, separate breeding lines for different colors.