Control techniques of Black Blight in Sheep

Black plague of sheep, also known as infectious necrotizing hepatitis, is an acute and highly lethal toxemia of sheep. Sheep and goats can occur.

Experts solve the disease:

⑴ pathogen: the pathogen of this disease is Clostridium norvegicus type B, which is Gram positive and bluntly round at both ends. Most of them are single or in two, and a few 3-4 bacteria form a short chain. The toxin can be divided into A, B and C types.

⑵ epidemic characteristics: it mainly occurs in the low-lying and humid areas where Fasciola hepatica is prevalent in spring and summer. Clostridium norvegicus exists widely in soil. When the sheep ate the feed contaminated by the spores of this bacteria, the spores entered the liver from the gastrointestinal wall. The normal liver is still hidden in the liver in the form of spores because of its high redox potential, which is not conducive to the transformation of spores into vegetative forms. When the liver is damaged by immature Fasciola hepatica and its redox potential decreases, the spores exist there, that is, they obtain suitable conditions, grow and reproduce rapidly, produce toxins, enter the blood circulation, and develop toxemia. Damage neurons and other cells related to life activities, resulting in acute shock and death. Therefore, the occurrence of this disease is often closely related to the infection of Fasciola hepatica. The disease mainly affects adult sheep over 2-4 years old, and goats can also be infected with the disease. the occurrence and prevalence of the disease are closely related to the infection of Fasciola hepatica.

⑶ symptoms: the clinical symptoms of this disease are very similar to sheep enterotoxemia and sheep fast plague, with acute onset and often sudden death. The course of disease in a few cases can be delayed to 1-2 days. The sick sheep showed flock, no food, elevated body temperature, difficulty breathing, lethargy, prone, and painless sudden death.

Pathological changes examined by ⑷: there was significant congestion in the subcutaneous vein, which made the sheepskin look dark and black. Congestion and bleeding of the pylorus and small intestine of the true stomach. There are a number of grayish-black necrotic foci on the surface and deep layer of the lungs, which are irregular and round, surrounded by a bright red hyperemia band, with a semilunar section.

⑸ diagnosis: a preliminary diagnosis can be made according to the clinical techniques of diseased sheep and the dark appearance of sheepskin. Do laboratory examination, collect the tissue at the edge of liver necrosis to make smear, staining microscopic examination, it can be seen that Clostridium norvegicus is thick and bluntly round at both ends, single or in pairs, and a few 3-4 bacteria form a short chain.

An expert treats diseases.

① prevention: control the infection of Fasciola hepatica, regular injection of sheep anaerobiosis vaccine, subcutaneous or intramuscular injection of 5 ml. When the disease occurs, move the circle to a high dry place, you can also use anti-Clostridium norvegicum serum for early prevention, subcutaneous or intramuscular injection of 10-15 ml, repeat once if necessary.

② treatment: a, slow course of disease of sick sheep, penicillin, intramuscular injection, 80-1.6 million units, twice a day. B, anti-Clostridium norvegicum serum, intramuscular or subcutaneous or intravenous injection, 50-80 ml, 1-2 times.