Key points of breeding parent fish in spring during gonadal development period from March to April

After the beginning of spring, the water temperature gradually increased, especially from March to April, the fish activity strengthened, developed rapidly, and the food intake also increased. This stage is an important period for the gonadal development of parent fish. Practice has proved that the cultivation of parent fish in spring is related to the success or failure of artificial reproduction of domestic fish, so it is necessary to pay attention to several points:

Fish pond

First, bait: grass carp parent fish to feed grass and concentrate mainly. According to the source of grass, generally feeding grass in the morning and concentrate in the afternoon should be fed on a fixed table. When there is a lack of green fodder in early spring, grass carp can be fed with wheat, grain sprouts, lettuce or green vegetable leaves, and later fed with ryegrass, water grass, etc., with a feeding amount of 2%-4% of the fish weight and finished in 2-3 hours. Herring must be fed with an appropriate amount of animal feed and live snail clams every 2 to 3 days. Silver carp and bighead carp are fed with powdered concentrate with a fish weight of 1% to 2% every day. One month before the induction of labor, if the water quality is fatter, the feeding can be stopped.

Second, fertilization: silver carp, bighead carp parent pond fertilization, every 7 days, apply organic fertilizer once, each time 100kg / mu, using sprinkling method. If the organic fertilizer is insufficient, you can apply some chemical fertilizer appropriately, once every 5-7 days, about 5 kg each time. Fertilization should be moderate to prevent excess. Apply fertilizer flexibly according to the fat and thin degree of pond water quality. The best water for silver carp parent fish pond is oil green and yellow green, and for bighead carp parent fish pond is tea brown. Keep transparency in 35~40cm. Fertilizer can be stopped half a month before induced labor.

Third, adjust the water quality: after the beginning of spring, due to the pond after a winter, physical and chemical factors in the water, plankton situation, is not conducive to energy conversion. So, before you start to feed and fertilize, replace half of the parent fish pond water and keep it 1 meter deep. The parent ponds of silver carp and bighead carp were flushed once every 20 days, adding 3cm of water every time, and grass fish ponds were flushed once every 10 to 15 days with 5~10cm added each time. One month before the induction of labor, you can flush every 2-3 days. When flushing, the flow rate should not be too fast to prevent parent fish from excessive physical exertion due to jacking water.

Fourth, pond patrol and disease prevention: patrol the pond once a day at dawn and evening, check whether the fish have floating head, eat more or less, water fat and thin, find problems and solve them in time. When the water temperature rises, the parent fish pond food farm is disinfected every 10 to 15 days, and each pond uses about 1 jin of bleach. Dissolve it with water and sprinkle it on and around the parent fish pond food ground.