Overwintering Management techniques of Monopterus Albus

The consumption of eel in the Spring Festival market increases. In order to obtain better breeding benefits, many farmers hoard eel for sale around the Spring Festival. In this way, how to overwinter eel becomes a difficult problem. How to manage eel to ensure safe overwinter?

The first method: overwintering in water

When the water temperature drops below 10℃, the eel stops feeding and hibernates in its burrow. In order to make eel overwinter safely, the pond body is built into a rectangle, north-south direction, the pond ridge is high in the north and low in the south, and the north pond ridge can be built into a windproof wall of more than 1.5 meters if conditions permit. The water level of the culture pond is kept at 30 - 50cm in the middle of September, and the water level is changed in the later stage without changing the water level. Meanwhile, the thickness of the soil layer in the pond is not less than 50cm, which is convenient for the eel to build a hole for overwintering and ensure that the water temperature at the bottom of the pond is above 0 DEG C. When the temperature is below 0℃ and the water surface freezes, the ice must be broken and the ice floes must be taken away to increase the dissolved oxygen in the water and prevent the eel from dying of hypoxia. When the eel is cultured in the net cage for wintering, the rotten aquatic plants at the bottom of the box are cleaned after the eel stops eating, and sufficient floating grass is ensured in the box for the eel to climb. The overwintering method in water is simple and easy to operate, but it is troublesome to catch in winter, and the survival rate is low, especially the overwintering mortality rate of eel cultured in net cage is relatively high.

The second method: overwintering in mud

When the water temperature is lower than 12℃, drain the pool water gradually to keep the soil at the bottom of the pool moist. Do not stir the soil at the bottom of the pool or change the shape of the surface after the eel stops eating. Can cover a layer of straw or straw curtain 10~20 cm thick on the soil surface, pay attention to the reserved space under the grass layer, and clear the ditch around the pool to drain water, which can play a role in ventilation and cold protection. The method has the advantages of low cost, simple operation, high survival rate of eel and small weight consumption, and has the disadvantages that special personnel is needed to take care of the eel at ordinary times, the catching is troublesome, and the eel seedling cannot be sold in time, so that the eel seedling is suitable for overwintering.

The third method: indoor winter method

When the water temperature drops below 10 DEG C, the eel in the pond is caught and cleaned, and stored in an indoor cement pond for cultivation. The area of the cement pond is preferably 3 - 8 square meters, the water depth is not more than 50 cm, the water is clean external pond water or well water, the temperature difference when water is fed is not greater than 3 DEG C, and the ratio of eel to water is preferably 1:2. Change the water once a day for the first 3 days, and then change the water once every 3~5 days. Clean up the metabolites at the bottom of the water every time you change the water, and ensure that the indoor temperature is 2~5℃. The method for temporarily culturing the eel is safer, has high survival rate, and can be sold at any time when the market is good; and the method has the disadvantages that the management and operation are troublesome at ordinary times, the weight consumption of the eel is large, and the eel is suitable for overwintering.

The fourth method: greenhouse winter method

when the water temperature is lower than 15 DEG C, the rice field eel is transferred into a plastic greenhouse for overwintering. The water level of the pool water in the shed is controlled at 50~70 cm, and the water peanut is placed, and the amount of the water is 1/3 of the water surface. When the water temperature is above 12℃, it is necessary to feed it properly until it stops eating, and pay attention to regulating the water quality to prevent a large number of metabolites from consuming oxygen. Keep the temperature in the shed at 2~8℃. Sunny days 11 a.m. to 3 p.m. pay attention to uncovering the film ventilation. When a large number of finless eel head out of the water surface, should pay attention to oxygenation. The method is beneficial to prolonging the growth time of the finless eel, increasing the weight, improving the survival rate, and being convenient to catch and sell; and the method has the disadvantages of high cost and complicated management operation.

The farmers can choose the most suitable method to ensure that the eel can survive the winter safely.