Breeding and management of fish in winter

First of all, there is a good opportunity to sell the fish that reach the commodity specifications as soon as possible in order to get back the funds. If the supply of aquatic products in the market exceeds the demand and the price is really low, hoarding ponds can be temporarily maintained to avoid the peak season. However, in the sale of commercial fish, we must control the heat, do not commit the deviation of "carving the boat and seeking a sword", and sell it when it is time to sell and compete for a suitable price.

Secondly, it is necessary to use the winter leisure time before and after the Spring Festival to calculate the labor cost of the year, and calculate the benefits, and make a good annual summary. It is necessary to select the best breeding forms and delivery methods from the annual summary, and sum up successful resumes and failed experiences, so as to lay a solid material foundation for the new year's fishing industry.

In addition, we have some other work to do.

1. Overwintering management of adult fish

It is necessary to strengthen the management of adult fish that are about to be listed on the market, especially to do a good job in preventing theft, and never turn into chaos as a result of temporary neglect, resulting in a "bumper harvest without a bumper harvest."

two。 Overwintering management of fish species

It is necessary to strengthen the overwintering management of fish species, deepen the water in the pond, and do a good job in overwintering in ponds.

3. Excavation and regulation of fish ponds

Comprehensive planning and design of newly excavated fish ponds should be carried out, and places with excellent water conservancy, excellent water quality and convenient transportation should be selected.

4. Complete the dredging and refurbishment of the pool in real time when there is no mistake in fishing.

In recent years, some fish pond contractors only pay attention to the immediate benefits, make efforts in planting, feeding, fertilization, and so on, neglecting the desilting work that needs to be done. Year after year, the silt at the bottom of the pond is getting thicker and thicker, and the same normal silt thickness of the pool is in Mr. 40cm. Some intensive ponds and ponds close to villages and towns have greater silting thickness, resulting in an improvement in the ecological premise of the pond. The disadvantages are as follows:

The main results are as follows: 1) the pool becomes shallow, the carrying capacity is reduced, and the water space of fish life becomes smaller, which directly affects the fish yield of unit area.

2) anoxia was formed in fish ponds. Because the mud contains a large amount of inorganic matter. In the low temperature season in summer and autumn, inorganic matter is oxidized and analyzed under the influence of bacteria, which constantly consumes a large amount of dissolved oxygen in the water, which often consumes the original little dissolved oxygen in the grass-roots water body of the pool, resulting in hypoxia. Under the premise of hypoxia, a large number of anaerobic bacteria breed, and ammonia, hydrogen sulfide and inorganic acids that are harmless to fish occur, and these materials are intensely aerophilic, which makes the pond water bear "oxygen debt". At night, due to the convection and exchange of high and low-level pool water, all the pond water bodies lack dissolved oxygen, and the pond fish lack oxygen. In case of unfavorable weather such as continuous rain, muggy low pressure, thundershower or the rise of winter wind, the anoxia in the fish pond is more serious, and it is very easy to cause the fish to die and become chaotic.

3) for the large amount of nitrogen-containing inorganic matter in the sludge, whether aerobic analysis is carried out under the influence of nitrifying bacteria or anaerobic analysis is carried out under the influence of nitrifying bacteria, the final product of both is ammonia. Ammonia is so toxic that it can restrain the development of fish and other aquatic organisms even at very low concentrations.

4) there are many fish parasites and pathogenic microorganisms in the sludge. When the amount of water in the pool becomes worse, the acidity increases, and the situation improves, the disease resistance of fish decreases, while the amount of pathogenic microorganisms grows and expands, resulting in the outbreak and prevalence of fish disease, resulting in loss. In recent years, the frequent outbreaks of silver carp, bighead carp and other fish in small pools and reservoirs are directly related to the serious siltation in the pool.

It is observed that the siltation of fish culture ponds usually increases at the rate of 5-10cm per year. Intensive culture ponds and pools close to villages and towns with sewage inflow have a faster siltation rate, and pond siltation has become an important part of limiting fish culture production in ponds. For continuous, stable and high yield of fish culture in ponds, desilting in summer must be at the forefront.

5. Clinical furnishings

According to the market demand, we should choose the breeding form and species according to the circumstances, set up the stocking attempt fairly, and release the fish species in real time. Many farmers are used to stocking after the Spring Festival, but it is not superstitious to do so. The temperature rises gradually in spring, and the scales of the fish are lax. due to the reasons such as pulling the net, transportation, delivery and so on, the fish body is easily injured, affecting the survival rate of fish species. Friends who want to cultivate grass carp can vaccinate grass carp at this stage.