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guinea pig(gĭn`ē), domesticated form of the cavycavy
, name for 14 species of South American rodents of the family Caviidae, including the domestic guinea pig. The wild cavies are usually small, rounded, and tailless, with fur of a uniform shade of brown.
..... Click the link for more information. , Cavia porcellus, a South American rodentrodent,
member of the mammalian order Rodentia, characterized by front teeth adapted for gnawing and cheek teeth adapted for chewing. The Rodentia is by far the largest mammalian order; nearly half of all mammal species are rodents.
..... Click the link for more information. . It is unrelated to the pig; the name may refer to its shrill squeal. Guinea pigs were raised by the Incas and have long been used as food in South America. They were first imported into Europe from Guiana in the 16th cent. There are a number of varieties, some with short, smooth hair and others with longer hair, and a great range of color combinations, including mixtures of black and white and many shades of brown. They have rounded bodies, large heads, and blunt noses and reach a length of 6 to 10 in. (15–25 cm) and a weight of 1 to 2 lb (450–900 grams). Females produce three to five litters, usually of three or four young, per year. The guinea pig's rapid reproductive rate and high resistance to disease make it a valuable laboratory animal; it is used for testing serums and antitoxins and for experiments in genetics and nutrition. It is also sometimes kept as a pet. It is classified in the phylum ChordataChordata
, phylum of animals having a notochord, or dorsal stiffening rod, as the chief internal skeletal support at some stage of their development. Most chordates are vertebrates (animals with backbones), but the phylum also includes some small marine invertebrate animals.
..... Click the link for more information. , subphylum Vertebrata, class Mammalia, order Rodentia, family Caviidae.
(Cavia porcellus), a mammal of the order Rodentia. The body length measures up to 35 cm; there is no external tail. The hind feet have three digits, and the forefeet have four. The color is brownish gray on top. The guinea pig inhabits open spaces in the foothill regions of Peru. A crepuscular animal, it lives in small groups in burrows that it either has dug itself or has taken over. It bears one to four young twice a year.
The guinea pig, or a closely related species, was domesticated by the Incas as a source of food and was imported to Europe in the 16th century. It is now widely used as a laboratory animal for medical purposes and physiological experiments. A number of breeds differing in the color and nature of the fur have been developed. In captivity, the guinea pig reproduces year-round, with each litter containing six offspring. The animal does not tolerate sharp fluctuations in temperature well.