How to prevent and control diseases and measures for farmers after floods.

Several points that aquaculture farmers should pay attention to after floods.

First, water disinfection kills pathogenic bacteria.

After the flood, due to a large number of silt, toxic and harmful substances on the surface and external water sources, the aquaculture water body is turbid, with low transparency and complex pathogens. In order to prevent the outbreak and spread of epidemic diseases after disasters, aquaculture water bodies should be disinfected in time. Water disinfectants generally include quicklime (dosage: 20-30g per cubic meter of water), bleaching powder (65438+ 0.0g per cubic meter of water), chlorine dioxide (0.2-0.3g per cubic meter of water), strong chlorine essence (0.3-0.4g per cubic meter of water) and bromochlorohydantoin (0.03-0.04g per cubic meter of water).

Second, the harmless treatment of dead fish.

A large number of dead fish often appear after the flood, so it is necessary to salvage them in time and treat them harmlessly quickly, and not to throw them around casually. Harmless treatment measures include: deep burial of dead fish, centralized high-concentration disinfectant treatment, centralized high-temperature treatment (including incineration) and so on. Among them, it is most effective to bury quicklime and bleaching powder above 1 m after disinfection. After the flood, it is necessary to strengthen the health awareness and health management of fishery workers, and insist on disinfection of tools, utensils and personnel for salvaging dead fish to prevent the outbreak of epidemic diseases.

Third, insist on patrolling the pond to find diseases in time.

In the critical period of resuming fishery production after the flood, it is necessary to patrol the pond in the morning and evening to observe and record the fish's activities, food intake, body color, water quality changes and weather changes, so as to make regular observation and analysis, effectively monitor the epidemic situation, make effective early warning and prediction of the epidemic situation, and prevent and control the outbreak and epidemic situation.

Fourth, accurate diagnosis and scientific medication.

After the flood, the aquaculture water is ecologically unbalanced, the water quality is unstable, and the fish are in a state of stress, which is prone to various diseases. At this time, we should pay special attention to the accurate diagnosis of diseases and the right medicine, avoid drug abuse and illegal drugs, avoid secondary fish accidents, ensure the stability of aquaculture environment, and ensure the health of fish and the quality and safety of aquatic products.

Five, the prevention and treatment technology of major diseases.

1, grass carp hemorrhagic disease:

Spray povidone iodine disinfectant or quaternary ammonium salt complex iodine disinfectant once every 10 day from July to September in the whole pool, with the concentration of 0.3~0.5 ml per cubic meter of water; Oral rhubarb, isatis root, houttuynia cordata and other natural antiviral Chinese herbal medicines. Preventive usage and dosage: Calculate the dosage according to the total weight of 0.5g/kg fish, weigh the medicine, boil it with warm fire 10 ~ 20min or soak it in boiling water for 20 ~ 30min, cool it, mix it with feed and feed it continuously for 3 days. Treatment usage and dosage: Calculate the dosage according to the total weight of 1.0g/kg fish. The drug treatment method is the same as before, and feed continuously for 5-6 days. Use of prepared bait: The above Chinese herbal medicines are directly added to the corresponding feed as additive components to make expanded granular feed bait, which can be directly used for the prevention and treatment of grass carp hemorrhagic disease. Inactivated cell vaccine is the most effective method to prevent grass carp hemorrhagic disease. Immunization by injection: it is suitable for 10 cm fish, injected at the base of ventral fin, with 0.2 ~ 0.5ml； per tail; Hypertonic soaking: suitable for fish species below 10 cm. Soak the fish in 2% salt water for 2~3 minutes, and then soak it in 5~ 10% vaccine solution (diluted with pool water) for 5~ 10 minutes. When the soaking solution is reused, it is necessary to add an appropriate amount of vaccine solution to maintain the vaccine concentration. Soaking summer flower fry: soaking in nylon bag with 2-3% vaccine concentration for 30-60 minutes; Transportation leads to prolonged soaking time and has no effect on fry.

2. Bacterial diseases of grass carp:

The gill rot, enteritis, erythroderma, printing disease, furuncle, bald mouth disease and rotten tail disease of grass carp are all caused by bacterial infection. Although bacterial pathogens are different, preventive and therapeutic measures are similar. Spraying quicklime (20~30 grams per cubic meter of water) in the whole pond has obvious effect on gill rot of grass carp; Spraying bleaching powder (1~2 times (65438+ 0 times every other day), chlorine dioxide (0.2~0.3 grams per cubic meter of water) or strong chlorine essence (0.3~0.4 grams per cubic meter of water) in the whole pond has obvious effects on bacterial diseases of grass carp. Garlicin (0.2g/kg body weight), enrofloxacin (0.05-0. 1g/kg fish body weight) or florfenicol (0.02g-0.05g/kg body weight) can be added to prevent and treat bacterial diseases of grass carp.

3, the main freshwater fish fulminant hemorrhagic disease:

The disease is caused by Aeromonas hydrophila infection, which mainly affects crucian carp and silver carp. The symptoms are hyperemia and bleeding on body surface, gill cover and fin base, exophthalmos, red and swollen anus and ascites in abdominal cavity. Spray the whole pool with disinfectant drugs such as quicklime (20-30g per cubic meter of water) or chlorine dioxide (0.2-0.3g per cubic meter) and strong chlorine essence (0.3-0.4g per cubic meter) once. Oral administration of enrofloxacin or florfenicol has obvious effect, and its dosage and usage are: enrofloxacin (0.05-0.1g per kilogram of fish) or florfenicol (0.02-0.05g per kilogram of fish) for 3 days. In addition, the disease is very sensitive to dragnet operation, and it can be effectively prevented by spraying copper sulfate (0.5g per cubic meter of water) in the whole pond 1~2 days before dragnet operation or spraying bleaching powder (0.5g per cubic meter of water 1g after dragnet operation).

4. Monopterus albus bleeding:

Hemorrhagic disease of Monopterus albus is one of the most serious diseases in cage culture, and its pathogen is Aeromonas hydrophila, which spreads quickly and has high mortality. The main symptom is that the sick eel does not eat, and the whole body is red and bleeding. The main causes of the disease are fish stress and pathogen infection caused by drastic changes in the culture environment. After the flood, it is easy to induce the outbreak of hemorrhagic disease of Monopterus albus due to the drastic change of breeding environmental conditions. When Monopterus albus eats normally, adding enrofloxacin (0.05-0.1g per kg body weight for 2-3 days) or florfenicol (0.02-0.05g per kg body weight for 2-3 days) in its feed can effectively prevent the occurrence of hemorrhagic disease of Monopterus albus. When treating the hemorrhagic disease of Monopterus albus, concentrated chlorine essence (0.3-0.4 g per cubic meter of water) or chlorine dioxide (0.2-0.3 g) can be sprayed in the whole pool (including cage), and florfenicol (0.05 g/kg body weight, fed continuously for 2-3 days) can be taken orally at the same time.

5, crab virus disease:

The virus disease of Eriocheir sinensis is caused by mixed infection of various virus pathogens, which has the characteristics of acute onset, rapid spread and high mortality. After the flood, due to the change of pond environment and water quality and the decrease of aquatic plants, it is easy to induce the occurrence and epidemic of river crab virus disease. The main symptoms of viral diseases of river crabs are: chest and feet twitching, sick crabs going ashore to eat grass and not eating; The blisters spit out are yellow-green, then turn brown-black. The prevention and treatment methods of viral diseases of Eriocheir sinensis include: improving the breeding environment and water quality, especially after the flood, properly lowering the water level to restore aquatic plants, spraying microecological agents, regulating water quality, improving transparency, avoiding the stress reaction aggravated by violent operation, feeding concentrated feed and adding various vitamins, and enhancing the physique and disease resistance of Eriocheir sinensis; Spraying povidone iodine (0.3~0.5 ml per cubic meter of water) in the whole pool can effectively kill viruses in water. After the onset, povidone iodine can be sprayed continuously for 2~3 times every other day 1 time; Oral natural antiviral Chinese herbal medicines such as rhubarb, isatis root, houttuynia cordata, etc. The usage and dosage are as follows: calculate the dosage according to the total weight of 1.0g/kg fish, weigh the medicine, boil it with warm fire 10-20min or soak it in boiling water for 20-30min, cool it and mix it with feed to make powder or feed it continuously for 4-5 days. When preventing and treating viral diseases of Eriocheir sinensis, it is necessary to ensure that Eriocheir sinensis eats enough drugs; In addition, an appropriate amount of antiviral western medicine (such as Virulin, dosage: 0.05 ~ 0. 1g/kg body weight, fed continuously for 3 days) can be added to the feed, and the effect is more remarkable.

In particular, sick crabs and dead crabs should be fished out in time, disinfected intensively and buried deeply. Never drain the water in the sewage pool.

6, crayfish virus disease:

Fulminant viral disease of crayfish is caused by viral infection, which can cause a large number of deaths. Usually, the symptoms of dead crayfish are not obvious, and laboratory detection technology can quickly diagnose them. In the prevention of crayfish viral diseases, immune promoters, such as oligosaccharides, chitosan and multivitamins, can be properly added to the feed to improve the antiviral ability of crayfish. The control measures of crayfish virus disease are the same as "crab virus disease". In particular, the dead shrimps should be fished out in time, disinfected centrally and buried deeply. Never drain the water in the sewage pool.

Prevention and control measures of animal diseases after floods

(a) do a good job of cleaning and disinfection of pens and the surrounding environment. The main thing is to ensure that there is no major epidemic after the disaster, that is, to eliminate pathogenic microorganisms in the natural environment. The germs in the soil will be washed away by rain and cause diseases. In order to eliminate pathogens in the environment, cut off the transmission route, prevent and control the epidemic of infectious diseases, and ensure the health of people and livestock, the internal and external environment of the farm and the disposal of livestock and poultry carcasses were disinfected.

(2) Dead livestock and poultry shall be treated harmlessly. Livestock and poultry found dead or with unknown causes should be treated harmlessly in time, and the principle of "four prohibitions and one treatment" should be followed: "Do not slaughter, eat, sell or transport, but must be treated harmlessly".

(3) Strengthen immunization. Immunization should be carried out according to immunization procedures, that is, pigs should be vaccinated with swine fever, foot-and-mouth disease and blue ear disease, chickens should be vaccinated with avian influenza, Newcastle disease, bursa of fabricius and new vaccines, ducks should be vaccinated with avian influenza and duck plague vaccines, and sheep should be vaccinated with bivalent foot-and-mouth disease, sheep pox and triple vaccine.

(4) Strengthen feeding management. After the flood, we will focus on preventing diseases such as Eperythrozoon, Toxoplasma gondii, Streptococcus and Leptospira. Antibacterial drugs, such as Toxoplasma gondii, amoxicillin and tetracycline, are added to feed, and nutritional drugs (such as jinweitai, electrolytic multivitamin and compound VB) are added to drinking water to improve the disease resistance of the body and prevent the feed from becoming moldy. Fungicide should be added to feed to ensure the safety of livestock feed and the sanitation of breeding environment.