Fish Diseases Can Be Predicted in Advance: Master the Common Fish Disease Prevention and Treatment Methods

For professional fish farmers, one of the most worrying problems is the occurrence of fish diseases. Because once a fish disease breaks out, fish die in large numbers, and such losses can be described as devastating. So what are the signs that fish are sick? Can they be predicted in advance? Below we will explain how to predict fish diseases in advance, and what the common fish diseases and prevention and treatment methods are. Professional fish farmers and small-scale farmers alike should read this carefully!

What are the warning signs and manifestations of sick fish?

1. The fish body becomes thin and blackened, and the fish swims alone away from the group or floats motionless by the pond edge.

2. The fish body floats to the surface and swims wildly or spins in circles. For example, in fish infested by Chinese fish fleas (Sinergasilus), the tail fin often protrudes above the water surface, and the diseased fish spins or swims on the water surface; when poisoned by pesticides or industrial wastewater, fish show excitement, jumping and colliding, then become paralyzed and die.

3. The fish's food intake suddenly decreases.

4. Dead fish suddenly appear.

What are the common fish diseases? How are they prevented and treated?

1. Gill rot disease: This disease mainly occurs in grass carp and black carp, and mainly occurs in autumn. It manifests as the gill filaments of diseased fish rotting and turning white; in severe cases, the cartilage at the ends of the gill filaments is exposed and often carries mud and dirt. The inner surface of the operculum is often corroded into transparent small windows.

Prevention and treatment: 1) Inject bacterial vaccine or traditional homemade vaccine.

2) Apply 1 g of bleaching powder or 1-4 g of Chinese gallnut per cubic meter of water by splashing over the whole pond.

3) Use 10 kg of quicklime plus 2.5 kg of salt per mu, mix with water and splash over the whole pond, once every 7 days, for 3 consecutive times.

4) Use 0.3 g of erythromycin for poultry per cubic meter of water and splash over the whole pond. The next day, feed erythromycin medicated bait, using 0.4 g of medicine per 10 kg of fish, and halve the dosage from day 2 to day 6.

2. Enteritis disease: This disease mainly occurs in grass carp and black carp, and often occurs from April to October. Symptoms include redness and swelling of the anus; in severe cases, the fin bases become congested, the fin rays split, and red spots appear on the abdomen; when the fish abdomen is opened, abdominal fluid can be seen, the intestinal tract is congested and inflamed, there is no food in the intestine, and there is milky yellow mucus or bloody pus.

Prevention and treatment: 1) Inject vaccine or.

2) Feed sulfaguanidine medicated feed, using 5 g of sulfaguanidine per 50 kg of fish, halve the dosage from day 2 to day 6, and feed once a day.

3) Garlic bulbs: use 0.5 kg per 50 kg of fish (add a small amount of salt), mix with concentrated feed and feed for 3 days.

4) Use 0.25 kg of rhubarb per 50 kg of fish, chop it up, add 2.5 kg of ammonia water and soak for 30 minutes, then add water and mix evenly to soak concentrated feed and feed.

3. Red skin disease: This disease mainly occurs in grass carp and black carp, and can occur in all four seasons. Symptoms include congestion, inflammation and scale loss on both sides and the abdomen of the fish body. The fin bases are congested, the fin rays split, and the ends rot.

Prevention and treatment: 1) Inject vaccine.

2) Orally administer 5 g of sulfathiazole per 50 kg of feeding fish (made into medicated feed for feeding), and halve the dosage from day 2 to day 6.

3) Apply 1 g of bleaching powder per cubic meter of water by splashing over the whole pond.

4) Use 10 kg of quicklime plus 2.5 kg of salt per mu and splash over the whole pond, once every 7 days, for 3 consecutive times.

4. Saprolegniasis (water mold disease): This disease is common between spring and summer and between autumn and winter. It is most likely to occur when the water temperature is 15-20 degrees C, and all kinds of farmed fish can be affected. When the hyphae on the body surface multiply in large numbers, the lesions on the body surface look like white cotton fluff, and the parasitic sites show congestion and decay, with much mucus on the body surface.

Prevention and treatment: 1) Operations should be as careful as possible to avoid injuring the fish body, pay attention to reasonable dense stocking, and do not make the overwintering density too high.

2) Clear the pond with quicklime, or use 2-3 g of Chinese gallnut per cubic meter of water, boil it in water and splash it over the whole pond.

3) Soak and wash the diseased fish with Kangmeining for 1 hour, with good results. For each mu of water surface, when the water depth is 1 m, use 2.5-5 kg of sweet flag (Acorus calamus), crush it for juice, add 0.5-1 kg of salt, then add 2-5 kg of human urine, mix and splash over the whole pond.

5. Gill mold disease: It mainly occurs in bighead carp, silver carp and mud carp fingerlings. It is common from May to October. The gills of diseased fish are pale white, sometimes with pinpoint bleeding, forming a red-and-white mottled symptom; explosive acute death often occurs.

Prevention and treatment: 1) Control the amount of fertilization and add new water in a timely manner.

2) Apply 0.7 g of copper sulfate per cubic meter of water by splashing over the whole pond.

3) Move the diseased fish into a pond with leaner water quality, and the disease can stop.

4) When the disease occurs, use 2.5 kg of mugwort leaves and 1.5 kg of sweet flag per mu, boil in 10 kg of water, add water and splash over the whole pond, for 2 consecutive days.

In addition, when the temperature changes greatly, it will cause a relatively large difference between the surface water temperature and the bottom water temperature of the pond, which may induce the occurrence of fish diseases. Therefore, farmers should pay attention to weather changes, strengthen management, and take corresponding measures to predict the occurrence of fish diseases.