Comprehensive prevention and treatment measures for hemorrhagic disease of domestic fish

I. the object of harm

Grass carp, crucian carp, mud carp, carp and even silver carp.

Second, symptoms

Punctate or patchy bleeding in the head, orbit, fin base, fish abdomen, Gill bleeding or pallor, sometimes ascites, and decay at the end of the fin.

Third, etiology

1. Fish diseases caused by bacteria are mostly caused by conditional pathogens, which will not occur before the deterioration of the water environment. Only when the various factors in the sediment and water become unsuitable for the survival of the fish, the resistance of the fish is reduced, and the bacteria in the water multiply in large numbers, the fish disease will break out.

2. Due to the long-term feeding of the fish pond, the fish discharged a large amount of feces, in which the incompletely digested organic matter polluted the bottom water, and the bottom of the pond became a hotbed for a large number of bacteria to multiply. After a large number of bacteria decompose organic matter, hydrogen sulfide, nitrite, ammonia nitrogen, methane, carbon dioxide and other toxic and harmful gases to fish accumulate in the water, and the fish live in it for a long time, and their physique will decline. It provides an opportunity for bacterial infection.

IV. Disease prevention measures

1. The author especially emphasizes that in order to improve the technology of fish culture, efforts should be made on the word "management", and the small links should not be ignored. Fish diseases must adhere to the principle of "giving priority to prevention, prevention is more important than treatment", careful management and comprehensive prevention and control should be achieved.

2. The "triad vaccine" injection of grass carp fingerling is one of the scientific and effective preventive measures.

3. Clear the pond thoroughly. During the period from the end of each year to February of the following year, the water temperature is low and the growth of fish is restricted. You can use this time to dry the pond to remove excess pond mud. It is best to drain the pond water and expose the bottom of the pond until it turns white and cracks.

4. A few days before the storage of water in the pond, use a large amount of quicklime (block) and sprinkle the whole pond with 100m / mu 150kg of bleach or 10m / 15kg of bleach.

5. The fish should be soaked and disinfected before entering the pond. The commonly used drugs are 3% saline, 1max 10000 potassium permanganate, 2max 10000 formalin and 4max 10000 dysentery, and the bath time depends on the water temperature.

6. Reasonable close culture and mixed culture, make full use of water body and feed, do not carry overloaded fish to the water environment.

7. Use medium and high-grade feed, use less raw materials (raw bran, corn, wheat, yellow flour, etc.) and use less low-grade feed, so as to reduce feces and relieve pond pressure by producing the same amount of fish.

8. It is advocated to pull the net every 20 seconds and 30 days. In the sunny morning and noon, the sediment with a lot of organic matter is stirred to the near surface of the water body, which can not only oxidize part of the organic matter by oxygen in the water, but also fully aerate, and inhibit the reproduction of anaerobic bacteria.

9. Immediately after pulling the net, quicklime should be disinfected with quicklime at a water depth of 15kg / mu or 20kg / mu or other water disinfectants, and quicklime should be recommended for disinfection.

10. In the hot season, new water should be added frequently, or part of the pool water should be replaced.

11. It is recommended to turn on the aerator at noon on a sunny day. Apart from turning on the aerator when rescuing the fish floating head, the aerator is turned on for 2 hours between 12: 00 and 3: 00 on a sunny day, which is also an effective measure to relieve pond pressure and prevent diseases.

12. Pay attention to the hygiene of the pond and try not to discharge unfermented human and animal feces directly into the pond.

13, weed diligently, feed to achieve the "four look", "four fixed" principle, leaving no residue, dead fish should be fished out of the pond, dig deep burial.

Fourth, look at the principles: look at the season, look at the weather, look at the color of the water, look at the eating of fish.

Four principles: fixed point, timing, quality and quantity.

14. Don't raise a certain kind of fish for many years in order to improve your immunity.