Emergency treatment of crayfish with hypoxia

High density leads to hypoxia: it is necessary to adjust the culture density in time and turn on the aerator for oxygenation. Excessive nutrition caused by hypoxia: quantitative, qualitative, timed feeding methods, feeding 1 bait every morning and afternoon. The area of aquatic plants is too large to cause hypoxia: the area of aquatic plants should be controlled between 30% and 50%, and the rotten aquatic plants on the water surface should be salvaged in time to ensure sufficient sunlight on the water surface. Water quality mutation causes hypoxia: quicklime can be applied once every 15 days to maintain water quality.

First aid for crayfish hypoxia

1. Reasonable stocking density

Generally, in the culture pond specially for breeding crayfish, 60-80 catties of lobster seedlings can be put into each mu culture pond from July to September every year, with a male to female ratio of 3:1, or 20 - 30,000 young shrimps of 2-4 cm can be put into spring.

2. Reasonable feeding

Crayfish like to come out at night for food, and have the habit of competing for food and gluttony. Therefore, when feeding crayfish feed, you can choose to feed once every morning and afternoon. At the same time, quantitative, qualitative and regular feeding methods should be adopted. During this period, sufficient feeding should be adopted, which is beneficial to the healthy growth of crayfish.

3. Control the area of aquatic plants

The area planted with aquatic plants should be controlled between 30% and 50%, and it should be dispersed to ensure that there is sufficient sunlight on the water surface of the culture pond.

4. Keep the water fresh

When putting lobster seedlings, it is necessary to ensure that the water quality in the culture pond is fresh enough and to maintain a suitable water level. During the culture process, quicklime should be applied once every 15 days.

5. Pay attention to weather changes

If the culture conditions permit, when the crayfish is anoxic, the aerator can be turned on for oxygenation, or a proper amount of oxygenator can be sprinkled into the culture pond.

II. Causes of hypoxia in crayfish

1. Different sizes

When the culture time of crayfish in the culture pond is relatively long, the adult shrimp of the previous season and the shrimp fry of the new season will coexist at the same time, so that it is easy to bully the weak. At the same time, in order to make full use of water resources, some farmers will also put fish, crab and other varieties in the culture pond, thus causing the density of culture to be large, resulting in the phenomenon of hypoxia of crayfish.

2, water quality mutation

The farmers who have just carried out breeding will generally worry about insufficient nutrition intake of crayfish in the early stage of breeding crayfish, so they will feed a large amount of bait, or put a large amount of vegetable cake after fertilization, which will easily lead to thickening of water quality in the breeding pond, especially in May and June, when encountering sudden weather change, it will lead to hypoxia of crayfish.

3. Overnutrition

In order to promote the growth of crayfish in the early stage, if excessive food is fed, the crayfish will be too full to resist hypoxia, which will also lead to hypoxia in crayfish.

4, lush grass

If the aquatic plants in the breeding pond grow luxuriantly, the whole pond surface will be almost covered by aquatic plants. In order to ensure that there are aquatic plants in the pond during the plum rain season, some farmers indulge the growth of aquatic plants, so it is easy to cause hypoxia of crayfish.

5. Water plants rot

In summer, water plants will die one after another, or will be cut off by crayfish. If they float in water and are not salvaged in time, they will deteriorate the water quality and cause crayfish to lack oxygen.