Prevention and control of red disease in Pelteobagrus fulvidraco

A little red disease of Pelteobagrus fulvidraco, also known as split head disease and head swelling disease, is a common disease in the process of Pelteobagrus fulvidraco culture in recent years, from seedling to adult fish. The disease is more common in 1-3 fish, especially in second-year-old fish, the water temperature is between 18-30 ℃ and 25-28 ℃ is more serious, so the disease peak period is from June to September every year, the disease course is relatively long, and the cumulative mortality rate is relatively high. When the temperature drops, the disease can be cured without treatment.

Etiological symptoms of a little red disease in Pelteobagrus fulvidraco

1. Etiology: it is also easy to occur when the pond water environment changes abruptly, such as inverted algae, or the water quality deteriorates, such as the decrease of pH value, the increase of ammonia nitrogen, the high level of nitrite, the low dissolved oxygen and the turbidity of water. In addition, feed nutrition, scratches, rushing for food, and mechanical injuries may all induce the disease, which is caused by "Edwardsiella" chronic infection. The route of infection is to infect olfactory cells through the nasal cavity, then enter the brain, and infect the skull through the meninges.

2. Symptoms: the top of the head of the diseased fish is red and swollen and fester until the skull is eaten, forming a long and narrow cavity, with serious symptoms of redness of the fins and a small amount of ascites in the internal organs. The sick fish will turn slowly above the head and under the tail on the water surface. Dissection showed that there were yellowish transparent fluid in the abdominal cavity, hemolysis in a few cases, yellow dull liver, bleeding spots or spots, swelling and congestion of spleen and kidney, gastric dilatation, severe hyperemia of gastric wall, gastrohydrops in some cases, redness of intestinal wall, shedding of intestinal mucosa, and yellow juicy liquid could be seen in cut intestines.

Diagnostic method of a little red disease in Pelteobagrus fulvidraco

Generally speaking, as long as you see the symptoms of "a little red" on the top of the fish's head, you can judge the disease, but because the diseased fish is weak, there are often a large number of rotifers parasitic on the gills, so some people are often misdiagnosed as rotifer, but this parasite infection is secondary.

Prevention and treatment of a little red disease in Pelteobagrus fulvidraco

The infection of a little red disease of Pelteobagrus fulvidraco is from the inside of the fish brain to out of the brain, so once the disease occurs, the effect of external disinfection and internal administration of antibiotics is not very good, so prevention is the key.

1. The weight can be controlled: the stocking density of Pelteobagrus fulvidraco is controlled at 2500 to 3000, and the suitable pond area and water depth are selected. generally, the area of the main culture pond is 3 million mu or less than 10 mu, and the water depth is 1.5 to 2 meters.

2. Increasing oxygen: the tolerance of Pelteobagrus fulvidraco to hypoxia environment is worse than that of other fish. In ponds with higher stocking density, an aerator should be set up to prevent fish from anoxic floating head, and the average power of aerator is 1.5KW per mu.

3. Improve the bottom frequently: use the bottom improver regularly to improve the geology.

4. Skillfully stabilizing water: regular use of water quality improvers and microbial preparations to maintain stable water quality.

5. Regular health care: choose high-quality feed and take vitamins regularly to increase the disease resistance and stress resistance of Pelteobagrus fulvidraco.

6. good at insecticidal disinfection: regular use of insecticides such as copper sulfate, regular use of disinfectants to eliminate hidden germs in fish, and removal of diseases in fish ponds