Prevention and treatment of common diseases of fish in early summer

In the early summer season, the water temperature is suitable, and all kinds of pathogens are easy to breed and breed, which is the season of fish disease. Fish disease can easily be caused by ignoring prevention. In particular, grass carp has a high mortality and great loss. In this paper, the symptoms and prevention methods of four major fish diseases are introduced as follows:

Water mildew:

Symptoms: local injury of fish body, scale shedding, surface moldy or long hair. Swimming disorder, reduced food intake, resulting in thin and died. The cause of the disease is mainly the injury of the fish after fishing, and the disease occurs after the disease invades the fish.

Prevention and control methods: (1) in the process of fishing, transportation and release, we should pay attention to protect the fish from injury. (2) when putting into the fish seed, the fish body can be soaked in 5% salt water for 5 minutes for 10 minutes. The soaking time depends on the temperature at that time and the bearing capacity of the fish. (3) sprinkle 30 kilograms of quicklime into the whole pool with water depth per mu.

2. Enteritis:

Symptoms: abdominal enlargement, erythema, protrusion, redness and swelling, abdominal microvascular congestion, the formation of thrombus, mucosal overflow. The epidemic situation is usually from April to September. The morbidity and mortality of 1-year-old and 2-year-old green grass carp reached 5% and 90%.

Prevention and control methods: (1) 1 mg of bleach per liter or 25 kilograms of quicklime can be sprinkled in the whole pool. (2) 250 grams of garlic, 200 grams of salt and 5 kilograms of bait were mixed and fed for 3 to 6 consecutive days for every 10,000 fish species or 50 kg adult fish.

Third, Gill rot disease (also known as aconite disease):

Symptoms: Gill decay, congestion, there is a skylight on the edge of the Gill, and the mucous membrane in the Gill sticks to the Gill filament, affecting breathing, resulting in asphyxiation and death. The popular season is from April to October. The water temperature was 28 ℃ ~ 30 ℃ and the pH value of pool water was 6.7 ~ 7.5. The Beginning of Autumn and the Autumn Equinox had the most serious disease.

Prevention and control methods: (1) 1 mg of bleach per liter can be sprinkled with water in the whole pool. (2) 10 grams of methamidophos were mixed and fed every 5 kg of bait. (3) 20000g methamidophos per mu can also be sprinkled in the whole pool. You can choose one of the above three methods.

4. Grass carp hemorrhagic disease:

Symptoms: mouth, jaw, top of head, eyes, red spots on the outside. The gills are bright red and the intestinal tract is also bright red. Intestines and liver are gray and white. There are blood spots on the swim bladder, gallbladder congestion, and lesions in all parts of the bladder.

Prevention and cure method: take rhubarb orally, mix 0.5kg 0.75kg rhubarb into 10kg bait for every ten thousand fish species or 50kg adult fish, or add appropriate amount of bean cake with 1kg flour, then stir 4 pieces of virus Ling in water and bait into slurry and add 50g salt for 3 days. The dosage will be halved from the third day.