Spring broodstock management measures

In order to grasp the growth and development of the broodstock and facilitate the oyster production, the broodstock pool should transfer the broodstock originally concentrated in the larger pond to a small pond with an area of ​​667 to 1500 square meters when the water temperature is around 10°C. Cultivate. Disinfect small ponds before pooling. When dividing the pool, the well-developed broodstock and the broodstock with poor growth and development are opened and raised. Density should be 120 kg to 150 kg per 667 square meters, and the broodstock in each pond can be used up in batches when the production is finished. This will not only facilitate the prenatal intensive cultivation of those broodstock that have poor growth and development, promote the rapid maturation of their gonads, but will not disturb other broodstock that have not yet been elicited when the broodstock is harvested. In the sub-pool, the brooding fish found to be sick and wounded can also be treated with drugs promptly.
After feeding and fertilizing, the gonads are in a stage of large growth and development, and require a large amount of nutrients. The broodstock of spring carp is cultivated in the spring, and it is still dominated by fertilized and cultivated food organisms. Dissolve the base fertilizer in the pool before pooling, and apply organic fertilizer from 300 kg to 500 kg per 667 m2 of fish pond. The squid brood pool should be given more manure, and the scorpion fish pond should be given more excrement. The amount of topdressing should be less than once in order to stabilize the water quality so that the pool water is both "live" and "fat", and the transparency is about 30 cm. 15 days before oxytocin, fertilization can be reduced or stopped. The spring cultivation of grass carp broodstock should be dominated by green material, supplemented with fine material. Pre-feeding of grain buds, malt, buckwheat cakes, etc., and early feeding of lettuce leaves, ryegrass, etc., and then transferred to only cast green feed. Near the ovulation period, the food intake of gonads of mature grass carp will be significantly reduced or even stopped feeding. Herring broodstock is mainly fed with snail meat, supplemented with bean cake or compound feed.
After the spring of the water patrol pond is in operation, the depth of the pool water will be controlled at about 1 meter, which will help the water temperature rise, promote the growth and reproduction of food organisms, and also be beneficial to the feeding of fish. Pro-fish ponds should always be flushed with fresh water to keep the water fresh and increase the amount of dissolved oxygen in the water. Early flushing, broodstock broodstock 10 times or so, broodstock broodstock once a week, gradually reduce the interval between flushing. Two weeks before the onset of labor, the brooding brood pool can be flushed once every other day. The broodstock of the grass herring can be flushed every day. It is advisable to infuse new water in the afternoon. Each time you flush 3 to 5 hours, increase the pool water by 15 to 20 centimeters.

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