CAVY, the name of several South American rodents of the family Caviidae (see RODENTIA) ; originally it was confined to the domesticated guinea-pig and its allies of the genus Cavia. (The word "guinea" here may be a corruption of "Guiana" but more probably it means "foreign") The true cavies are small, self coloured animals, with short, rounded ears and no tail. They are partly diurnal and live in burrows. The diet is vegetarian and their cries are faint squeaks and grunts. Unlike the prolific guinea-pig, which begins to breed at two months old and may be the parent stock of a thousand individuals in a year, the wild cavies breed only once a year, producing one or two young at a time. These are born in a very advanced stage of development and are able to feed themselves the following day.
Cavies are widely distributed in South America. The original of the domestic race is C. cutleri of Peru. C. boliviensis is found at great elevations in the Andes. The restless cavy of Brazil is C. porcellus. The Patagonian cavy or mana (Dolichotis pata chonica) resembles a 'hare in shape and habits, but lives in a burrow. Fossil species of this genus, of which there is a second smaller type in Argentina, have been found in Brazil and the Argentine.