Six conditions affect the feeding of fish

In the process of intensive fishery production, the management of feed feeding is one of the main links in the whole production management, and the decrease of feed intake of fish often occurs in the process of feed feeding. According to the different conditions in production, the reasons for the decrease of feed intake of farmed fish are as follows:

The first situation: the fish is suffering from the disease, resulting in a reduction in fish feed intake. Such as Carassius auratus endosporidiosis, grass carp three diseases, spotted forktail disease, enteritis and other diseases, the food intake of fish decreased significantly. When grass carp and crucian carp have a large number of rotifers parasitic, it will occur in front of the feed table swimming phenomenon, affecting food intake, food intake is reduced.

This situation occurs in the early stage of the disease, once there is a reduction in food intake, we should pay attention to it, check the fish immediately, prevent and treat the disease according to the specific situation, and the food intake can return to normal after the fish return to health.

The second situation: poor water quality, resulting in a reduction in fish feed intake. When the dissolved oxygen in the water is insufficient, the water quality is aging, the ammonia nitrogen, nitrite nitrogen and hydrogen sulfide exceed the standard seriously, and the water body is polluted by high copper, the food intake of fish will decrease.

If the food intake of fish is poor in the morning and good at noon and evening, it is mainly due to insufficient dissolved oxygen in the water, aging water quality, or excessive ammonia nitrogen, nitrite nitrogen and hydrogen sulfide.

In view of this situation, water quality control is mainly carried out. As the old saying goes, to raise a good pond of fish, first raise a pond of water. Water quality control is an important part of scientific aquaculture, and attention should be paid to keeping the aquaculture water body fat, alive, tender and cool in the process of culture. Fertilizer: the transparency is 30cm ~ 40cm, light green, there is an appropriate number of phytoplankton, the water body can provide abundant natural bait for fish. Living: excellent algal phase, diurnal and periodic changes in transparency and acidity, and regular changes in ammonia nitrogen, calcium, phosphorus and other concentrations. Tender: the water color is green, there are many new phytoplankton and probiotics, which is conducive to the growth of fish. Shuang: the water quality has no oily and greasy feeling, and there are few dead algae. The main method of regulation and control is to turn on the aerator in time every day, often add new water, raise the water level, promote the use of beneficial biological agents, improve substrate and water quality, and often replace part of the old water during the period of high temperature, preferably every 15 days, use photosynthetic bacteria or EM bacteria.

The third situation: due to the mass reproduction of trichaeophyllum in the water, producing a large number of fish toxins, cytotoxins, hemolytic toxins, neurotoxins and so on, algal toxins are activated and reached a certain concentration, resulting in a reduction in fish food intake.

When the content of total ammonia in water is more than 0.25 mg / L, trichaeophyta can not become the dominant species. Therefore, the preventive effect can be achieved by regularly applying ammonia fertilizer, urea, nitrogen and phosphorus compound fertilizer and organic fertilizer to the pond to stabilize the total ammonia at 0.25 mg / L ~ 1 mg / L. In the early stage of the diseased fishing pond, 100 kg of clayey soil per mu of water was washed into mud, and then sprinkled in the concentrated area of diseased fish at the four corners of the pond, and then sprinkled throughout the pond. Changing a lot of water is an effective method.

The fourth situation: drug influence, resulting in a reduction in fish food intake. In order to prevent and cure fish disease, trichlorfon, copper sulfate, chlorophenylguanidine hydrochloride and pyrethroids are used to reduce the food intake of fish, which usually lasts for 2 ~ 3 days.

Less or no highly toxic drugs should be used, and aquatic drugs with high efficiency and low toxicity can be used to reduce the effect of drugs on fish. Change the water or detoxify the fish in time after the fish is restored to health.

The fifth case: a sudden change in temperature leads to a reduction in fish food intake. When the cold air suddenly comes, the food intake of snakehead and soft-shelled turtle can be reduced by 1/2 to 2/3; in hot and muggy weather, the food intake of fish is reduced to varying degrees. The effect can be eliminated by temperature adjustment, such as shading or adding an insulating shed.

The sixth situation: fish will reduce or stop feeding during the breeding season. Therefore, this situation should be avoided as far as possible in the process of commercial fish culture. in the process of crucian carp culture, reducing flushing water to fishing ponds and improving water quality are effective ways to shorten the growth affected by reproduction.

In the process of production, effective measures can be taken flexibly according to the actual situation to reduce the adverse effects.