In winter eel farming, pay attention to the prevention and treatment of enteritis disease

In winter, water temperature drops, changes in beneficial bacteria in the water, and changes in dissolved oxygen in the water body adversely affect the survival of eels, thereby causing a decline in eel constitution and immune function, and ultimately triggering enteritis disease, so attention must be paid to prevention and treatment.

In winter, the temperature difference between day and night is large. Some eel farms are eager to sell eels and often neglect changes in the farming environment, including: drops in water temperature, changes in beneficial bacteria in the water, changes in dissolved oxygen in the water body, and so on. These environmental changes adversely affect the survival of eels, thereby causing a decline in eel constitution and immune function, and ultimately triggering enteritis disease. Its main symptoms are: red and swollen anus, and most diseased eels have a large amount of ascites in the abdominal cavity. Some eels have an enlarged spleen, brown in color, floating feces on the water surface, and white dysentery in the water. The specific causes and treatment methods are as follows:

1. Enteritis caused by temperature difference changes

Some eel farms, eager for the eels to grow, frantically add feed and ignore changes in the external natural environment. When cold air suddenly arrives, the water temperature drops sharply and the temperature difference between day and night becomes larger, thereby causing indigestion in eels and triggering enteritis. The main symptoms are: intestinal congestion, floating feces on the water surface, and white dysentery. The specific treatment methods are as follows:

1. External disinfection

Chlorine dioxide 0.5-0.8 mg/L, disinfect once every two days.

2. Oral administration

Digestion-aiding drugs and per kg of feed add 5 g of salt, 5 g of Chuanxinlian, and 5 g of Dijincao (boil Chuanxinlian and Dijincao, then mix the feed with the medicinal liquid).

2. Enteritis caused by water quality deterioration

As eels grow larger and the amount of bait fed increases, the excrement of the eels also continuously increases, while the water exchange volume is still kept at the original basis. Some farms, due to water shortage, even exchange less water than before, thereby causing continuous accumulation of organic matter in the pond.

These organic substances rot and ferment in the pond, producing various harmful substances, causing various water quality indices in the pond to exceed standards, such as high ammonia nitrogen and nitrite. In particular, high nitrite is not only highly toxic and has strong toxic side effects on eels, but also requires consuming a large amount of oxygen in oxidation-reduction reactions to be reduced to nitrate. In addition, the massive reproduction of plankton in the water (such as: chironomid larvae, Epistylis, etc.) often causes dissolved oxygen in the pond to decrease. In some farms, dissolved oxygen in the water even drops below 3 mg/L. This easily causes indigestion in eels. The main symptoms are: eels swim weakly and are dispersed, and the mucus on the body surface appears zebra-like; eels gather together in front of and behind the aerator and at the water inlet; the food intake of eels decreases significantly, and some stop eating. The treatment methods are as follows:

1. Stop feeding for 2-3 meals.

2. Use drugs that can degrade nitrite to degrade nitrite (such as: Xiaoxiao Suxiao 1-1.5 mg/L, Yakejing 1-1.5 mg/L) to adjust water quality.

3. Use potassium permanganate 3 mg/L + 90% crystalline trichlorfon 0.3-0.6 mg/L to kill plankton and increase dissolved oxygen in the water.

4. After the eels' constitution recovers, start feeding from a low feeding amount and gradually increase the feeding amount.

5. Oral administration: rhubarb soda tablets 8 tablets + berberine hydrochloride 5 g + malt 5 g + Xiaoyan Lidan tablets 8 tablets (malt must be boiled, then mix the feed with the medicinal liquid).