Prevention and treatment of fish diseases

Measures such as scientific stocking, improving the disease resistance of fish, controlling pathogens and applying pesticides are mainly adopted. Before stocking the fish pond, the whole pond should be cleaned up, that is, the water in the pond should be drained, the surface silt at the bottom of the pond should be removed, and the pond should be exposed to the sun and weeds should be removed to eliminate the spawning grounds of pathogens and parasites. You can also sprinkle quicklime, bleaching powder, tea cakes, etc. Enter the pool to clean the pond. Bait and feces of aquatic plants, feeding places and breeding tools for fish should be disinfected with bleaching powder before feeding or using.

In order to prevent the international spread of pathogens, imported and exported fish should be quarantined. China's Regulations on the Quarantine of Import and Export Animals and Plants in People's Republic of China (PRC) and the Interim Provisions on the Quarantine of Freshwater Fish at Ports have clearly defined the scope, objects, methods and treatment methods of quarantine. All pathogens that are extremely harmful to fish and lack effective prevention and control measures, such as infectious pancreatic necrosis virus of salmon and trout, myxoma of brain that causes rotational disease, are listed as the main quarantine objects. The drugs used to prevent and treat fish diseases mainly include halogen (bleaching powder, sodium chloride, iodine, etc. ), heavy metal salts (copper sulfate, ferrous sulfate, copper chloride, potassium dichromate, etc. ), sulfonamides (sulfadiazine, sulfathiazole, sulfaguanidine, etc. ), furans (furacilin, furazolidone, etc. ), banned fishery drugs), organophosphorus pesticides (trichlorfon, etc. ), antibiotics (penicillin, streptomycin, chloramphenicol, chlortetracycline, oxytetracycline, erythromycin, etc. ), Chinese herbal medicines (Chinese tallow, rhubarb, garlic, Euphorbia humifusa, amaranth, etc. ), and other bactericidal dyes such as malachite green, methylene blue, quicklime, sulfur, borax, potassium permanganate, etc.

There are usually four application methods: ① bag (basket) hanging method. A bag or basket filled with drugs is hung in the water around the food table or food field in a fish pond to form a drug action area, and fish automatically enter and leave the area within the tolerable drug concentration range, and the drug action kills pathogens on the body surface and gills. Generally used for prevention or early treatment. Copper sulfate and ferrous sulfate are commonly used to hang bags to control hyphomycosis and bream disease of grass carp, and bleaching powder is used to hang baskets to control red skin disease and gill rot of herring and grass carp. (2) Immersion method. Soak the fish in a container with high concentration of drugs, and force the drug to be administered in a short time, so that the pathogens on the fish body surface or gills are killed, but the fish itself is not harmed. Commonly used salt concentration of 2% and nitrofurazone concentration of 20ppm are used to prevent and treat diseases such as white-headed mouth disease and gill rot caused by myxobacteria. The concentration of potassium permanganate is 10 ~ 20 ppm to control the third generation filariasis and dactylosis. ③ Sprinkling water method. Is the most commonly used method. That is to say, the concentration of drugs that can kill a pathogen and are safe for the fish itself is sprinkled all over the fish pond to kill pathogens on the fish body surface, gills and water. Using this method, it is necessary to accurately calculate the volume and dosage of pool water. The mixture of copper sulfate 0.5 ppm and ferrous sulfate 0.2ppm is often used to treat wheel disease, fish wave bean disease, flagellate disease, herring disease and so on. The concentration of rhubarb is 2.5~3.75ppm, which is used to treat white-headed mouth disease and gill rot of myxobacteria. 0.25~0.5ppm trichlorfon crystal was used to treat finger and toe cysts. ④ Oral method. Mixing drugs into bait to make fish palatable particles is a drug prevention and treatment method for internal organs diseases. Raw garlic, salt and sulfadiazine are commonly used to prevent and treat herring and grass carp enteritis, and sulfathiazole or the mixture of sulfur powder and iodine tablets is used to prevent and treat herring coccidiosis. ⑤ Injection. For example, some viral or bacterial fish diseases can be prevented by vaccination, and injection of penicillin and streptomycin can treat printing diseases and postpartum injuries of grass carp, silver carp and bighead carp. 1, Galla Chinensis: 2-3 grams of Galla Chinensis decoction can be sprinkled all over the pond per cubic meter of water to prevent and control fish white skin disease, red skin disease and gill rot. 2. Acorus calamus: 4-5 kg of Acorus calamus and 4-5 kg of Ricinus communis are used to break each mu of water into slurry. After a little soaking, the dregs and juice are splashed all over the pool to prevent and treat fish enteritis, gill rot and erythroderma.

3. Verbena: 0.5 kg of Verbena and 0.5 kg of Plantago asiatica per 100 kg of fish, add appropriate amount of water and boil for 30 minutes, take the medicine juice, mix it with rice sugar, let it cool, knead it into balls and put it on the table, and feed it continuously for 5-6 days, which can prevent and treat enteritis of grass carp and herring.

4. Garlic: 65,438+0 kilograms of garlic is used for every 50 kilograms of fish, mashed into juice, and mixed and fed 65,438+0 times a day for 3-6 days, which can prevent and treat various fish enteritis.

5. Ricinus communis: Fresh leaves or twigs of Ricinus communis 15 kg per mu of water surface are folded into several small bundles and placed around the bait table for two times to prevent fish from scabbing.

6. Pinus massoniana: fresh leaves of Pinus massoniana 15 kg and 25 kg of finely ground water are sprinkled into the pool per mu of water surface; Or feed the fish with 500 grams of crushed Pinus massoniana needles and 50 grams of salt per 5 kilograms of fish, which can prevent and treat fish skin diseases, gill rot and enteritis.

7. Willow leaves: 65,438+00-65,438+05 kilograms of fresh willow leaves are used per mu of water, tied into bundles and put into water, and replaced 65,438+0 times after the leaves are rotten, which can cure grass carp enteritis, gill rot and red skin disease.

8. Ginger: 6 kg of ginger, 6 kg of maple leaf, 5 kg of mulberry leaf 1.8 kg, and 5 kg of Cinnamomum camphora leaf per mu of water surface, mixed and decocted for 2 hours, and 0.6 kg of pig blood and 0.2 kg of salt 1.2 kg can cure bacterial gill rot of grass carp.

9. Pepper: 0.25 kg of pepper powder and 0.5 kg of fresh ginger are used per mu of water surface, and water 10 kg is added to make spicy ginger soup, and cold water 15 kg is added to fill the pond, which can cure fish and melon diseases.

10, tobacco leaves: 0.5 kg of surface tobacco leaves per mu, boiled in water for 2 hours, sprinkled in the whole pond, can cure fish enteritis, gill rot and red skin disease.

1 1, leek: 2.5 kilograms of leek per mu with a water depth of 0.8 meters, chopped and added with 0.2 kilograms of salt, mixed and taken once a day for 5 days, which can cure grass carp enteritis. 1, it is advisable to prevent diseases first and seek medical advice after avoiding diseases.

It is difficult to observe the symptoms of fish at the beginning of the disease. When it is cured, sick fish often eat less or not, which brings difficulties to medication.

2, appropriate regular prevention, to avoid civil air defense.

The onset of fish has a certain periodicity. For example, fish are prone to water mold in early spring and late autumn, and the old "three diseases" of grass carp and herring are prone to occur in early summer and Mid-Autumn Festival, while the period of high water temperature in summer is the high incidence season of explosive fish diseases. According to this rule, fish diseases can be prevented in advance.

3. Comprehensive prevention should be taken to avoid single drug.

Fish disease is the result of comprehensive factors, so comprehensive measures must be taken to prevent fish disease, inhibit pathogens, improve water environment and improve fish disease resistance. Including thorough cleaning of ponds, fish disinfection, regular water injection and application of quicklime, scientific fertilization and feeding, regular internal and external treatment, etc.

4, appropriate low temperature disinfection, avoid high temperature medicine bath.

Medicinal bath is an important method to prevent and treat fish diseases. Generally, when stocking fish in low temperature season, it is carried out in wooden barrels or pots. In summer, this method is very harmful because the water temperature is very high.

5, appropriate rotation of medication, to avoid a single drug.

If only one drug is used to prevent and treat diseases in water, all kinds of pathogenic bacteria and parasites in fish will develop drug resistance and reduce the effect of drug use. Therefore, drug rotation should be actively advocated, but acidic drugs and alkaline drugs should not be mixed.

6. Take medicine regularly and avoid taking medicine at any time.

The use effect of fish medicine, especially the overflow medicine in the whole pool, is closely related to water mixing, dissolved oxygen and illumination. High water temperature, rich dissolved oxygen and strong illumination can speed up the effective speed of drugs, improve the curative effect and reduce the side effects of drugs. Therefore, the prevention and treatment of drugs should be carried out in a sunny afternoon.

7, appropriate amount, avoid adding.

The dosage of various fish medicines is determined by many experiments, which can effectively prevent and treat fish diseases with little side effects. If used in excess, it will not only increase the cost, but also cause drug damage.

8. Non-metallic containers should be selected for storing and dissolving drugs, and metal containers should not be used.

Fish drugs are mostly synthetic drugs, which are unstable in chemical properties and easy to react with metals, and their components and properties change. Therefore, containers made of nonmetallic materials such as ceramics, wood and plastics should be used to store and dissolve fish medicine.