J Tajik - Department of Clinical Sciences, School of Veterinary Medicine, Shahid Bahonar University of Kerman,Kerman, Iran
A Khodakaram Tafti - Department of Patobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
A Derakhshandeh - Department of Patobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
T. Tajik - Department of Patobiology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran

Black leg has been reported in a variety of animals, but is of the most importance in cattle and sheep. A20 days old Holstein dairy calf was examined because of anorexia and lameness from 2 days ago. The calf was depressed, tachypneic, tachycardic, and had a body temperature of 38.5ºC. Both hind limbs proximal to the tarsal joint were markedly swollen, firm and painful. No crepitation was noted on palpation. The calf had bruxism, stiffness of gait and unwillingness to move. At necropsy, massive necrosis of thigh muscles which caused dark discolorated tissue with metallic sheen, large amount of thin sanguineous exuda andabundant gas bubbles were evident in the underlying tissues. Histopathologic examination revealed extensive degeneration and coagulative necrosis of muscle fibers and supported a diagnosis of black leg. No vaccination against Clostridium chauvoei was applied in the herd and the calf did not receive notable maternal antibody. Providing sufficient maternal antibody or early vaccination of the susceptible newborn calves should be considered in the endemic regions.

black leg, sucker calf, dairy, maternalantibody, endemic regions