Malignant catarrhal fever is a sporadic, frequently fatal, and generalized viral disease of cattle, pigs, domesticated buffaloes and free-living deer and moose, and a wide range of antelopes, African buffaloes and bison in captivity. More than 150 ruminant species are susceptible to MCF virus infection based on serological evidence, and clinical disease has been described in over 30 of them, almost exclusively in captivity.