Sheep black plague is an acute, highly lethal toxemia of sheep and goats caused by Clostridium perfringens (Clostridium perfringens type B). The disease is characterized by the occurrence of necrotic lesions in the liver parenchyma, so it is also called infectious necrotizing hepatitis.

The epidemiological characteristics of the disease are: sheep over 1 year old are more frequent. 2 to 4 years old obese sheep are most frequent, goats can also be incidence. It mainly occurs in spring and summer in low-lying wet areas. Because these areas are prone to sheep liver flake schistosomiasis, only when the liver flake schistosome damage to the liver, the spores of this clostridium can rapidly grow and multiply, producing toxins, causing toxemia, so the occurrence of this disease is related to liver flake schistosome infection.