Fish clonorchiasis

Main pathogens: trematodes, cercariae, metacercaria.

Harmful species: silver carp, bighead carp and so on.

The suitable period for prevention and control is from May to August.

Identification features: the diseased fish are black and thin, and at the initial stage of acute infection, the diseased fish make a jumping struggle on the surface of the water, or swim rapidly in the water, but when the physical strength is exhausted, they swim slowly, head down and tail up, losing balance, the fish body bends or the head and orbit are seriously congested; the cornea of fish eyes is cloudy and milky white in chronic infection, and the lens falls off into blind eyes in serious cases.

Control methods: (1) the best scheme is to cull the first intermediate host, the solid snail and the final host gull, to cut off the life cycle of trematodes and to achieve the purpose of radical cure. (2) every cubic meter of water is sprinkled with 0.5 grams of copper sulfate in the whole pool and repeated after 1 day. (3) 0.25 grams of dibutyltin oxide per kilogram of fish was fed for 5 days. (4) 0.2g / kg of dichlorophenol per kilogram of fish was fed with 0.2g / kg of dichlorophenol for 3 days. (5) bind the aquatic grass (bitter grass is the best) or dry grass into several bundles, pile them up in the water around the pond in the evening to trap trematodes, pick them up the next morning and kill them in the sun.