Analysis on how to increase the yield of green shrimp in shrimp and crab mixed culture ponds

Mixed culture of shrimp and crab is a culture mode promoted by fishery science and technology in Xiangcheng District. In recent years, when the price of river crab has been repeatedly impacted by the market, the price of green shrimp is relatively strong. Therefore, under the condition of ensuring the growth of river crab, tapping the production potential of green shrimp has become an effective way to achieve high efficiency of mixed culture of shrimp and crab. Here are some technical points on how to improve the yield of shrimp in mixed culture ponds:

1. Optimize the stocking structure and grasp the production potential of shrimp in spring.

For the stocking structure, we need to choose a reasonable stocking mode according to our own Tangkou conditions on the basis of learning the advanced model. From March to June, the size of the river crab is smaller and the biomass is less, so we should give full play to the production potential of the spring prawns. We can first culture the river crabs in the ring ditch, and the large space outside is used for planting aquatic plants and cultivating green shrimp. In this way, not only aquatic plants can fully grow, but also green shrimps have plenty of room for growth. In addition, when eating early in spring and the water temperature above 15 ℃, a small amount of nutritious feed should be fed to supplement the physical strength of green shrimp, so that it can be shelled and grow smoothly, put on the market as soon as possible, and gain price advantage.

2. Insist on replenishing autumn prawns

Some farmers think that green shrimp will breed in the pond, so they do not put autumn seedlings, so the yield of shrimp in autumn is very low. In fact, due to the non-synchronization of time, pond water quality and environmental conditions, the survival rate of green shrimp is not high, and the specification is not neat. Therefore, it is necessary to replenish about 25000 autumn shrimp seedlings per mu to ensure a better yield of commercial shrimp and prawn in autumn.

3. Pay attention to water quality

The water quality of river crab culture is relatively clear, but the growth of green shrimp needs a certain degree of fertility, and the water quality needs to be alive and cool. Too thin water quality is not conducive to the growth of green shrimp. Therefore, it is necessary to use biological fertilizer and microbial preparation to regulate the water quality and control the moderate fertility of the water body, which not only meets the growth needs of green shrimp, but also does not affect the growth of river crab.

4. Reasonable collocation of aquatic plants

Eloe algae is generally planted in shrimp and crab ponds in Xiangcheng District. Elorella is easy to survive, but not resistant to high temperature, so it is necessary to plant a variety of aquatic plants to complement each other. Generally can be paired with verticillium verticillata, bitter grass and so on.

5. Feed nutrition and feeding

In shrimp and crab mixed culture ponds, in order to ensure that shrimp and crabs can get enough feed, the feeding technique can be improved, and feed with slightly lower protein content (for example, 36% of 38% protein) (accounting for 70% of the total feed) can be fed to river crabs first, and then feed with slightly higher protein content (for example, 38% of the total protein content) (accounting for 30% of the total feed) to shrimp and crabs, so that all shrimp and crabs can get adequate nutrition.

6. Use a microporous aerator

As the green shrimp has a high demand for dissolved oxygen, it is necessary to keep sufficient dissolved oxygen in the pond. In view of the fact that the impeller aerator is easy to kill the surrounding shrimp and crabs, it is recommended to use a microporous aerator to increase oxygen.