Management measures for efficient culture of fish fry

Feed feeding

According to the nutritional needs of fish fry at different growth stages, the fry are reared in three stages as follows:

1. The first stage: from the 1st to 7th day, the whole length of Yuhua pond was 0.7cm to 1.2cm. It was fed with fresh pig blood. 500g of pig blood was used for every ten thousand heads per day, and water was sprinkled along the edge of the pond. It was fed three times (9 o'clock, 14:00 and 18:00 respectively).

2. The second stage: Yuhua went down to the pond for 8 ~ 14 days, with a total length of 1.2 cm to 2.0 cm. Feeding crushed peanut bran (40mm 60 mesh granules), peanut bran tastes fragrant to attract fish, high nutritional value, but also fertilizer water, 500g per 10,000 tails per day, dry sprinkled throughout the pond, fed twice (once at 10:00 and 17:00 respectively).

3. The third stage: Yuhua went down to the pond for 15 ~ 50 days, with a total length of 2.0 ~ 5.0 cm. The formula feed with more than 32% protein content was crushed into 1020 mesh pellets, and the daily feeding amount was about 8% of the total weight of fish fry, which was fed in two times (once at 10:00 and 17:00 respectively). Adhere to the "four fixed", and adjust the amount of feed according to the actual situation.

Staged water injection

In order to meet the requirements of activity space, water quality and nutrition of fish fry in different stages, water injection by stages is an effective measure to improve the survival rate and growth rate in the process of fish fry cultivation. The specific method of operation is: the shallow water goes into the pond, that is, the water depth is about 0.6 meters when the fish flowers go into the pond, and then according to the water color and the growth of fish fry, water is injected once every 4-5 days, each time 10-20 cm, and the water depth is finally stable at 1.2-1.5 meters. When injecting water, it must be filtered with a dense net to prevent wild fish from entering the fry pond with the water.

Daily management

Patrol the pond once every morning and evening, carefully observe the water quality, fry activity and eating, timely fish out sick fish, dead fish, immediately check, if diagnosed fry disease, should take necessary prevention and control measures. In addition, check whether there are loopholes in the dike ridge, whether the drain is in good condition, and pay attention to escape prevention.

Divide the pond in time

After about 25 days of cultivation, when the total length of fish fry reaches 2.5 cm to 3.0 cm, fish fry should be screened and sparsely reared in ponds in a planned way, otherwise the survival rate of fry culture will be low. Because fish fry grow rapidly in the cultivation stage, there will be inconsistent ontogeny, and the phenomenon that big fish eat small fish, especially in the case of insufficient feeding. The author had such an experience that 500000 fry with a total length of 2.5cm were released in the pond. due to the failure to divide the pond in time, 100000 fry with a total length of about 5.0cm were obtained after 30 days of cultivation, and the survival rate was only 20%.