Clostridium novyi is a gram-positive, obligate anaerobic bacteria of the class clostridia.
It is responsible for Infectious necrotic hepatitis/black disease, which is an acute disease of sheep, and cattle. Hepatic necrosis is caused by exotoxins of C. novyi type B in liver damaged by Fasciola hepatica It causes dark discoloration of skin caused by subcutaneous venous congestion, and causes gas gangrene and myositis. It may be involved in cutaneous lesions and causes big head in rams - oedema of subcutaneous tissues of the head, neck and cranial thorax; necrotising lethal alpha toxin