Prevention and Treatment Methods for Schistosomiasis in Dairy Cattle

Schistosomiasis is a zoonotic blood fluke disease mainly caused by Schistosoma japonicum. Cattle have the highest infection rate, and the lesions are also relatively obvious; the main symptoms are anemia, malnutrition and stunted development. In China it occurs mainly in the Yangtze River basin and southern regions, and rarely in the north.

Pathogen: The adult Schistosoma japonicum is long and thread-like, with separate sexes, but in the animal body it is mostly found in a paired, embracing state. The eggs are passed out of the body with the feces, form miracidia in water, invade the intermediate host, the Oncomelania snail, develop into cercariae inside its body, and escape from the snail into the water. Infection can occur through the mouth or the skin.

Symptoms: In acute cases, the sick cow mainly shows a rise in body temperature to above 40°C, with irregular intermittent fever, and may die from severe anemia leading to general exhaustion. Most cases seen are chronic; the sick cow shows only indigestion, retarded development, diarrhea and blood in the stool, and gradually becomes emaciated; if feeding and management conditions are relatively good, the symptoms are not obvious and the animal often becomes a carrier.

Prevention and treatment: To do a good job of preventing schistosomiasis, comprehensive control measures must be taken: ① Manage feces well; cattle manure is the source of infection for this disease. Therefore, in conjunction with collecting manure, the feces should be gathered together and given harmless treatment, such as piling and composting or fermentation, to kill the eggs. ② Change the feeding and management methods; in areas where schistosomiasis is prevalent, the water drunk by cattle must be chosen from snail-free water sources to avoid infection by cercariae. Treatment: Use praziquantel, 30-40 mg per kg body weight orally once, or 30 mg per kg body weight by intramuscular injection.