The guinea pig is an important meat-producing animal in Peru as well as in several other South American countries. They are held in different kinds of systems, from the small backyard breeders with few animals to the large commercial farms with thousands of guinea pigs. One of the major issues at the farms is animals dying of unknown causes. Salmonellosis is often considered as a major cause, but samples for confirmation are rarely taken. It has been known for a long time that Clostridium difficile (C.