Treatment of Gill rot of farmed carp in autumn

I. morbidity and symptoms

A total of 8 boxes of carp were cultured in cage in Tumenzi Reservoir in 2005. the seedlings were put into operation from the end of April to the middle of September, and the disinfectants were used every half month, and the bait was given every 20 days. Fungicides and insecticides are used alternately for prevention. No fish disease was found in the early stage of culture. Due to past experience, the disease is rare in autumn and prevention is neglected. The disease began on October 1, and from October 1 to 3, there were at least 1 dead fish in each box, and most of them were 3-5, and the dead fish reached 10-15 kg per day. From October 4 to 8, the number of dead fish in each box was as little as 3 to 10 fish per day, and the number of dead fish reached 20 kilograms per day. From October 8 to 11, the number of dead fish decreased gradually after treatment, and the disease was basically controlled by October 13. The main symptoms of diseased fish are: slow swimming, loss of appetite, swimming up and down. Fishing out the dead fish for observation, some Gill filaments rotted, some petal Gill, some open skylight. Because it is a grass-roots unit, there is no microscope to make a diagnosis. According to the previous experience and the comprehensive conditions of various reservoirs in this area, the method of both insecticidal and bactericidal treatment was adopted.

II. Treatment methods

1. Disinfectant treatment from October 3 to 5, the mixture of copper sulfate and ferrous sulfate (5 ∶ 2) was sprinkled with a concentration of 2 g / m3 (the water body was calculated according to the water body in the cage). As the drug sprinkled in cage culture was easy to spread, it was the same with the use of trichlorfon as described below. From October 6 to 11, long-acting trichlorfon was sprinkled with a concentration of 1.25 g / m3.

two。 Oral bait treatment began to feed bait on October 6. The bait is made into particles by adding feed directly to the feed factory. The fish medicine is a net mixture of Baoji'an (fish type) and virus. Baoji'an is mainly composed of levofloxacin with a dosage of 1 g / kg feed. The main components of the virus are ribavirin, enrofloxacin and VC, with a dosage of 2 g / kg feed.

After internal and external treatment, the disease was basically controlled on October 13, and no dead or diseased fish were found after October 15, and the fish disease was basically cured.

Third, experience

Gill rot disease is a kind of fish disease with rapid infection and long course of disease, which is difficult to control once it occurs. There are mainly two kinds of Gill rot disease: parasitic Gill rot disease and bacterial Gill rot disease. The prevention of aquaculture in the early stage was better, and there was no fish disease, but in the later stage, due to the neglect of prevention, the fish got sick and caused unnecessary losses. Therefore, in the process of breeding, prevention should be given priority to, prevention is more important than cure, and prevention should be taken before it happens.