Abstract
Ferrets (Mustela putorius furo) belong to the ancient family Mustelidae, which is believed to date back to the Eocene period, some 40 million years ago. The taxonomic groups in the family Mustelidae, as recognized by Nowak (1999), include 67 species in 25 genera from North, Central, and South America; Eurasia; and Africa. No other carnivore shows such diversity of adaptation, being found in a wide variety of ecosystems ranging from arctic tundra to tropical rainforests. Mustelids have retained many primitive characteristics, which include relatively small size, short stocky legs, five toes per foot, elongated braincase, and short rostrum (Anderson, 1989). The Mustelinae is the central subfamily of the Mustelidae. The best-known members of the Mustelinae are the weasels, mink, ferrets (genus Mustela), and the martens (genus Martes) (Anderson, 1989). The genus Mustela is divided into five subgenera: Mustela (weasels), Lutreola (European mink), Vison (American mink), Putorius (ferrets), and Grammogale (South American weasels). The smallest member of the Mustelidae family is the least weasel (Mustela nivalis), which weighs as little as 25 g, and the largest member is the sea otter (Enhydra lutris), which can weigh as much as 45 kg (Nowak, 1999).