How to diagnose and treat parasitic diseases in fish? Detailed technical points
Diagnosis and treatment techniques for parasitic diseases in fish
I. Sporozoosis. Sporozoa are the most diverse, most widely distributed and relatively harmful group of parasites in aquatic animals. Currently the more serious ones include coccidiosis, crucian carp myxosporidiosis, round myxosporidiosis, disc-shaped myxosporidiosis, and crucian carp myxosomiasis, Sinocyclocheilus myxosomiasis, etc. After fish are heavily parasitized by sporozoa, symptoms such as emaciation, reduced appetite, darkening of the body surface and abdominal distension appear.
Prevention and treatment methods. 1. Excess sludge at the bottom of the pond must be removed, and quicklime or chlorine-containing disinfectants should be used to clear the pond so as to kill dormant spores. 2. When purchasing fry and fingerlings, prevent the introduction of infection sources. Before the fry and fingerlings are put into the pond, soak them in povidone-iodine for 15 minutes to 20 minutes. 3. Feed high-quality bait to enhance the disease resistance of the fish. When sporozoa parasitism is found, add 1.5% "Baochongsha" to the feed and feed continuously for 3 days, and on the 4th day splash "Yuchongmie" over the whole pond once.
II. Cestodiasis. There are many species of tapeworms harmful to fish, mainly including Bothriocephalus and Ligula. Bothriocephalus mainly parasitizes the intestines of grass carp, silver carp, bream, crucian carp and common carp, causing the diseased fish to lose weight, darken in body color, and swim alone away from the group, etc. When Ligula parasitizes fish, the diseased fish has an enlarged abdomen, loses balance, swims on its side or with the abdomen upward. Dissection shows that the body cavity is filled with ribbon-like worms, the internal organs are compressed, deformed and atrophied, and the diseased fish also loses commercial value because of being thin but with a large abdomen.
Prevention and treatment methods. 1. Before stocking, thoroughly clear the pond with quicklime to kill adult worms and eggs in the water. 2. Add 200 g to 280 g of "Yuchong Sumie" to every 100 kg of feed, make medicated bait and feed continuously for 3 days. 3. 5 days to 7 days after feeding the medicated bait, splash 0.6×10-6 "Shamie Haiyin" or "Baiduqing" over the whole pond to prevent secondary bacterial infection. 4. For every 10,000 fish, grind 250 g of pumpkin seeds into a powder slurry, mix it evenly into 0.5 kg of bran and feed, continuously for 3 days.
III. Chilodonelliasis. It mainly attacks the gills and skin of fish and uses their mucus as nutrition. When fish are parasitized by Chilodonella, the gills and skin are damaged and a large amount of mucus is secreted, causing breathing difficulty in the fish. The fish body becomes thin and dark, movement becomes sluggish, and death follows soon after. A water temperature of 5°C to 18°C is the epidemic season for this disease, and it harms many species of freshwater fish.
Prevention and treatment methods. 1. Thoroughly clear the pond and disinfect with chlorine-containing preparations to kill the pathogens. 2. Before fingerlings are put into the pond, soak them in 8 mg/L copper sulfate or 2% salt solution for 20 minutes. 3. Soak diseased fish in copper sulfate solution at a concentration of 8×10-6 for 30 minutes, and splash a mixture of 0.7×10-6 copper sulfate and ferrous sulfate (5:2) over the whole pond.
IV. Lernaeosis. Lernaea is a large parasite visible to the naked eye. It mainly parasitizes the gills and epidermal tissues of many freshwater fish and sucks nutrient fluid, thus causing the parasitized areas to become red, swollen and inflamed, with red spots appearing, and making them susceptible to attachment by water mold or infection by other pathogens. Diseased fish are restless and anxious, reduce food intake, gradually become emaciated and die. In recent years, lernaeosis has occurred rather seriously and caused relatively great harm.
Prevention and treatment methods. 1. Thoroughly clear the pond with quicklime. 2. In affected ponds, splash a mixture of 0.7×10-6 copper sulfate and ferrous sulfate (5:2) over the whole pond. 3. When the disease occurs, soak the fish body in (10 to 30)×10-6 potassium permanganate for more than 1 hour. 4. For each mu, use 10 kg to 12 kg of pine branches and leaves, tie them into 5 to 6 bundles, insert and hang them around the feeding area, or crush them, soak out the juice and splash it over the whole pond. 5. Applying fertilizer or adding fresh water to change the water quality can also cause the worm bodies to drop off and has a certain therapeutic effect.
Prevention and treatment methods. 1. Excess sludge at the bottom of the pond must be removed, and quicklime or chlorine-containing disinfectants should be used to clear the pond so as to kill dormant spores. 2. When purchasing fry and fingerlings, prevent the introduction of infection sources. Before the fry and fingerlings are put into the pond, soak them in povidone-iodine for 15 minutes to 20 minutes. 3. Feed high-quality bait to enhance the disease resistance of the fish. When sporozoa parasitism is found, add 1.5% "Baochongsha" to the feed and feed continuously for 3 days, and on the 4th day splash "Yuchongmie" over the whole pond once.
II. Cestodiasis. There are many species of tapeworms harmful to fish, mainly including Bothriocephalus and Ligula. Bothriocephalus mainly parasitizes the intestines of grass carp, silver carp, bream, crucian carp and common carp, causing the diseased fish to lose weight, darken in body color, and swim alone away from the group, etc. When Ligula parasitizes fish, the diseased fish has an enlarged abdomen, loses balance, swims on its side or with the abdomen upward. Dissection shows that the body cavity is filled with ribbon-like worms, the internal organs are compressed, deformed and atrophied, and the diseased fish also loses commercial value because of being thin but with a large abdomen.
Prevention and treatment methods. 1. Before stocking, thoroughly clear the pond with quicklime to kill adult worms and eggs in the water. 2. Add 200 g to 280 g of "Yuchong Sumie" to every 100 kg of feed, make medicated bait and feed continuously for 3 days. 3. 5 days to 7 days after feeding the medicated bait, splash 0.6×10-6 "Shamie Haiyin" or "Baiduqing" over the whole pond to prevent secondary bacterial infection. 4. For every 10,000 fish, grind 250 g of pumpkin seeds into a powder slurry, mix it evenly into 0.5 kg of bran and feed, continuously for 3 days.
III. Chilodonelliasis. It mainly attacks the gills and skin of fish and uses their mucus as nutrition. When fish are parasitized by Chilodonella, the gills and skin are damaged and a large amount of mucus is secreted, causing breathing difficulty in the fish. The fish body becomes thin and dark, movement becomes sluggish, and death follows soon after. A water temperature of 5°C to 18°C is the epidemic season for this disease, and it harms many species of freshwater fish.
Prevention and treatment methods. 1. Thoroughly clear the pond and disinfect with chlorine-containing preparations to kill the pathogens. 2. Before fingerlings are put into the pond, soak them in 8 mg/L copper sulfate or 2% salt solution for 20 minutes. 3. Soak diseased fish in copper sulfate solution at a concentration of 8×10-6 for 30 minutes, and splash a mixture of 0.7×10-6 copper sulfate and ferrous sulfate (5:2) over the whole pond.
IV. Lernaeosis. Lernaea is a large parasite visible to the naked eye. It mainly parasitizes the gills and epidermal tissues of many freshwater fish and sucks nutrient fluid, thus causing the parasitized areas to become red, swollen and inflamed, with red spots appearing, and making them susceptible to attachment by water mold or infection by other pathogens. Diseased fish are restless and anxious, reduce food intake, gradually become emaciated and die. In recent years, lernaeosis has occurred rather seriously and caused relatively great harm.
Prevention and treatment methods. 1. Thoroughly clear the pond with quicklime. 2. In affected ponds, splash a mixture of 0.7×10-6 copper sulfate and ferrous sulfate (5:2) over the whole pond. 3. When the disease occurs, soak the fish body in (10 to 30)×10-6 potassium permanganate for more than 1 hour. 4. For each mu, use 10 kg to 12 kg of pine branches and leaves, tie them into 5 to 6 bundles, insert and hang them around the feeding area, or crush them, soak out the juice and splash it over the whole pond. 5. Applying fertilizer or adding fresh water to change the water quality can also cause the worm bodies to drop off and has a certain therapeutic effect.