Summary of high-yield techniques of grass carp in two seasons a year! Aquaculturists, come and have a look.

Grass carp is one of the four major domestic fish, which is loved by the market, but the culture cycle of grass carp is relatively long, and many farmers are reluctant to raise it. But at present, by using high-yield technology, grass carp with two harvests a year can be achieved. Let's take a look at the summary of high-yield techniques of grass carp in two seasons a year.

First, prepare before raising fish

1. Pond selection

Choose ponds with sufficient water sources, no pollution sources in the upstream, convenient drainage and irrigation, and perennial micro-running water. The suitable size of the pond is 0.2 ha ~ 0.67 ha and the water depth is 1.5 m ~ 2 m.

2. Pond disinfection

10-15 days before stocking, disinfect the pond with 7kg / 667m2 / 10kg / 667m2 bleach or sprinkle the whole pool with 75kg / 667m2 rice lime while it is hot.

2. Fish fingerling restocking

The first season begins around the Spring Festival, mainly stocking grass carp species, properly mixed culture of carp, carp, silver carp and bighead carp. The stocking density of grass carp is 350 g / fish ~ 400 g / fish, the stocking density is 600 / 667 square meters, the stocking density of carp is 200 ~ 250 grams / fish, the stocking density is 500 / 667 square meters, the stocking density of carp is 100 grams / 150 grams / fish, the stocking density is 100 / 667 square meters, the stocking density of silver carp is 300 ~ 400 grams / fish, and the stocking density is 100 / 667 square meters. The size of bighead carp is 150 g / tail ~ 200 g / tail, and the stocking density is 20 pieces / 667 square meters, so as to ensure that all the bighead carp can be listed in the pond before the Dragon Boat Festival. The second season begins after the Dragon Boat Festival, all grass carp species with a tail weight of 150g ~ 200g are released with a stocking density of 600 / 667 square meters. the general tail weight can reach more than 1.25kg by the end of the year. Before stocking, all fish species are bathed in 4% saline solution for 10 minutes and 15 minutes to prevent various bacterial diseases and water mildew.

3. Feed feeding

1. The type of feed. The special sedimentation pellet feed of grass carp with crude protein content of 28% to 30% was selected, and the particle size of pellet feed was 2.5 mm in the early stage of culture and 3.5 mm in the later stage of culture. The feed coefficient was 1.6.

two。 Installation and use of automatic bait feeding machine. The machine adopts 220 volts single-phase lighting power supply, 90 watts of power, 80 kilograms of material box volume and 80 square meters of feeding area. The automatic bait feeding machine can be installed by the pond next to the management room, and the power switch is installed in the management room. When feeding, as long as you turn on the indoor power switch, the automatic feeding machine can sprinkle the pellet feed evenly into the pond regularly and intermittently according to the set procedure. After feeding the feed (the feeding time of each meal is set to 1 hour), the power supply can be turned off automatically. An automatic bait feeding machine can be installed in ponds with an area of less than 0.67 hectares.

3. Feeding method. The feeding ability of fish is closely related to the water temperature. The feeding ability of fish is weak when the water temperature is low, and the feeding ability of fish is strong when the water temperature is high. Therefore, the daily feeding in the early stage of culture is calculated according to 2%-3% of the total weight of grass, carp and carp in the pond, and 5%-6% in the later stage of culture. In case of muggy heat, cold current, torrential rain and other weather can be reduced as appropriate. Feed twice a day.

IV. Daily management

For the high-density intensive production mode, the daily management work is mainly to maintain good and stable water quality, with emphasis on preventing hypoxia and flooding ponds.

1. Add new water. Persist in filling water with a small flow day and night. In case of serious floating head, the amount of water should be increased.

two。 Patrol the pond early. Light floating head begins at 5: 00 to 6: 00 in the morning and disappears after the sun comes out at 7: 8, which is normal. Heavy floating head starts from 3: 00 in the middle of the night, if no timely measures are taken, it will lead to the death of fish in Fantang at 5 ~ 6 o'clock. Therefore, get up at 3 am to patrol the pond once, especially in Lesser Fullness of Grain, Grain in Beard these two seasons are most prone to heavy floating head. If heavy floating head is found, measures such as adding new water and turning on the aerator to increase oxygen should be taken in time to prevent flooding.

3. Start the aerator at the right time. Ponds with an area of less than 0.67 hectares are equipped with a single-phase water jet aerator of 0.75 kilowatts. When the floating head is light, it can be turned on at 5: 6 am to 8: 9 am when the floating head disappears and then stops. In the two seasons of Lesser Fullness of Grain and Grain in Beard, in case of thunderstorm or muggy weather, the machine should be turned on at 12:00 in the morning to stop at 8: 9 the next day.

V. Disease prevention and control

Adhere to the policy of "prevention is the first, prevention is more important than cure". When patrolling the pond, if it is found that there is a grass carp cluster at the inlet and the fish body blackens, it is a sign of disease. At this time, the whole pool was sprinkled with 1 mg / L bleach for 2-3 days to stop the disease. There is generally no disease during the second season. The main diseases in the first season were grass carp "three diseases" and hemorrhagic disease.

VI. Timely fishing

After five months of breeding, all kinds of fish species put in in the first season have basically met the commodity specifications, and all of them will be caught and listed by the end of May. At this time, around the Dragon Boat Festival, the supply of fresh fish is off-season, and the market price is high. After more than five months of careful breeding, all kinds of fish species released in the second season will meet the commodity specifications by the end of December, and all of them should be caught and listed on the market.