The od-toed ungulates are browsing and grazing mammals which compose the order Perissodactyla. The odd-toed ungulates (animals having an odd number of toes on each hoof) are usually large, have relatively simple stomachs and a large middle toe. In contrast to the Ruminant Artiodactyl ungulates, perissodactyls are hindgut fermenters; that is, they digest plant cellulose in their intestines rather than stomach.