Technique of single culture of Macrobrachium rosenbergii in pond

Disinfect newly built shrimp ponds or shrimp ponds modified with fish ponds should be thoroughly disinfected with drugs before stocking. The commonly used disinfection drugs for clearing ponds are quicklime, bleaching powder, tea meal and so on. Cleaning pond disinfection is usually carried out one month before the release of shrimp fry. There are two methods: dry cleaning pond disinfection and water cleaning pond disinfection. Dry cleaning and disinfection with 65 kilograms of quicklime or 5 kilograms of bleach per mu. Clean the pond with water and disinfect it with quicklime 125-150 kg per mu (water depth 1 m) or bleach 30-50 g per cubic meter of water.

After the shrimp ponds were cleaned and disinfected, the shrimp ponds were fed and fertilized 7 days before seedling release. The pond was first injected with water 20 to 30 centimeters deep and 200 to 300 kilograms of fermented organic fertilizer per mu. After a few days in the sun, the water level increased to 50-60 centimeters.

The number of desalinated shrimp seedlings per mu is 15000 ~ 20 000 or 8000 ~ 12000 per mu. After about 150 days of culture, the yield per mu can reach 100,150kg. With good water quality and high culture technology, the stocking capacity of shrimp fry can be more than 30,000 per mu (0.7-1cm desalination seedlings). The following points should be paid attention to in stocking shrimp fry: the desalination salinity of shrimp fry is less than 0. 3%; the temperature difference of pond water is less than 2 ℃ during stocking; and the fry is released in the upwind.

Feed feeding Macrobrachium rosenbergii was mainly fed with animal feed in the early stage of culture. If there is more plankton feed in the pond water, the freshly released Macrobrachium rosenbergii seedlings can not be fed within one week; if the pond water is clearer and the biological feed is less, it will be fed 4 times a day. After 15 days, they were fed 3 or 4 times a day. In the middle and later stage, there were 2 to 3 times of daily feeding, and the amount of feeding in the evening accounted for 1/2 to 2/3 of the total daily feeding. The feed had better be processed into balls and fed more. At the initial stage of stocking, the shrimp seedlings were fed at a water depth of about 0.3 meters around the pond, and gradually fed to the deep water as the shrimp grew up, but the water depth could not exceed 0.7 meters.

Daily feed consumption can be seen in the following table, which is generally adjusted every half a month. The actual production should be flexibly mastered according to the changes of season and weather, as well as shrimp intake and activities.

The main points of daily management are as follows: (1) early breeding. First, breeding feed organisms; second, timely feeding, shrimp seedlings after stocking, especially desalinated seedlings of 0.7-1cm, low foraging ability, appropriate increase in feeding amount, timely feeding of high-quality palatable feed; third, the early water level is relatively shallow, it is necessary to prevent the pond water from being too fat and add new water in time. Fourth, pay attention to the water temperature, especially the temporary cultivation of early seedlings, because the air temperature is low, the control of water temperature should be particularly strengthened to avoid sharp changes in temperature caused by stocking, water exchange, cold air and other reasons, resulting in the death of seedlings. (2) the middle stage of culture (from July to August). During this period, the water temperature is high, and shrimp disease is easy to occur. Attention should be paid to water quality regulation, disease prevention and feeding, so as to avoid feed deterioration, excess feeding and floating head phenomenon; regular sprinkling of quicklime and bait; ponds with oxygen-increasing equipment should make full use of the equipment to increase oxygen. (3) in the later stage of culture. During this period, the shrimp grows rapidly, the individual is large, and the food intake increases greatly, so the feeding amount should be increased in time; pay attention to the phenomenon of floating head of Macrobrachium rosenbergii in the pond; collect shrimp in time.