Daily management techniques of mixed culture of river crab and green shrimp

Water quality management

According to the growth of shrimp and crab, fresh water should be added frequently. In the early stage, it is required to inject new water once every 15 to 20 days. In the prosperous food and growing season, the water is injected 2 or 3 times a week, or even once every evening. Pay attention to shrimp, crab concentrated molting do not flush, otherwise it is easy to cause adverse effects on molting shrimp and crab.

Start the aerator at the right time

Generally speaking, it opens at noon on sunny days and in the middle of the night on rainy days. The start-up time is long in hot weather, short in cool weather, short at noon and long in the middle of the night (it can only be stopped after sunrise in the morning). If you find any signs of floating head, drive as soon as possible.

Molting stage management

The main results are as follows: 1. Sprinkling and fertilizing for external use should avoid the middle stage of molting.

2. Master the law of molting and predict the next molting peak.

3. Detoxification after changing water one week before the peak period of molting, and adding ecdysone.

4. Reduce the amount of feed during the peak period of molting, and pay attention to the relatively quiet environment.

Disease prevention and cure

In the process of breeding, adhere to prevention, usually every 15 days with quicklime 10g / cu m whole pool sprinkle. At the same time, biological agents are used to regulate water quality and improve the ecological environment of water body.

Harvest

Green shrimp can be harvested in the first half of the year and all in the dry pond at the end of the year. Macrobrachium rosenbergii and Penaeus vannamei can take the way of rotation to avoid centralized listing and reduce the culture density, which is beneficial to the growth of prawns. River crabs usually start fishing on the market in October.