The survival rate of farmed fish during the wintering period is low, and the proportion of fish body weight loss is high. After the winter, the fish body is weak, grows slowly, and prone to disease, which is an important reason for low fishery production and poor economic returns. How to make the fish safe for winter, reduce the winter weightlessness of the fish, and how to quickly restore vitality and rapid growth after winter? These have always been difficult problems for fish farmers. To solve the above problems, we mainly have the following countermeasures: The larger the size of timely feed concentrate fish, the more robust the body, the more resistant to cold and the ability to tolerate hypoxia, and the lower the mortality during wintering. If the fish is not ideal enough before wintering, it should be fed with sufficient feed containing a lot of fat and protein so that it can meet the wintering specifications as soon as possible. If it is because the price is not ideal and ready to sell the fish after the Spring Festival, the fish should also reasonably feed nutrient-rich concentrates before wintering, in order to fatten and grow, to accumulate energy, and enhance cold resistance. Appropriate feeds for oils and fats For general warm-water fish such as mackerel, grass carp, squid, etc., when the water temperature is below 13°C, the activity of amino acid oxidative metabolic enzymes is significantly reduced, and fish will use fat as the main energy source, which requires feed Oil content should be increased appropriately. Cold-water fish need more fat than warm-water fish. In areas with low water temperature, the protein content of formulated feed before winter can be properly reduced, but the content of oil must be guaranteed. The total amount of fat in fish feeds should be kept above 5%, and the fat content in adult fish feed should be kept above 4%. However, in areas where the wintering season is long, the use of animal fats should be stopped one month before wintering. Because of the lower melting point of animal fats, it is easy to see the hardening of the oil in the cultured fish during the wintering period. When the grease in the hepatopancreas, mesentery, etc. hardens, it will affect the normal physiological function of the fish, and even cause the fish to die during wintering. Because the fish is very sensitive to the freshness of the oil, and the fat is easily oxidized and rancid, the oxidized oil not only reduces the nutrient level of the fat-containing feed, but also the aldehydes and ketones produced during the oxidation process are toxic to the fish liver. , so that the fish growth rate, fish thin and so on. Raw materials, such as extruded soybeans, rice bran and silkworm cocoons, should be used with limited or no use before they are overwintering. Adding wintering spirit and wintering spirit in feeds is a functional premix that the scientific research department needs to develop for the wintering period of fish, which can promote the accumulation of fish nutrient substances, significantly increase the fish body fatness, and ensure nutrient supply during winter. Before wintering and one month after wintering, 0.2%~0.3% of total fish material can be added. Pay attention to the prevention and treatment of diseases Before wintering, we must conduct a disease inspection on commercial fish that are ready for winter and require the fish to be robust, vigorous, and free from disease and injury. If the commercial fish is more serious, it is not appropriate to enter wintering ponds. If the fish is mild, it should be treated first, and then be turned into wintering ponds after being cured. Before the fish enters the pond, disinfect the fish body first, and soak the fish body with 3%~5% saline for 10~20 minutes. You can also add salt and baking soda to each 500g of the mixing agent in each cubic meter of water. Dip the fish for 30 minutes. Maintaining good water quality in the pond during the wintering season is also an important measure to prevent disease. Some old water can be replaced before wintering under conditional water exchange, and water quality can be adjusted by photosynthetic bacteria and Bacillus before winter , Reduce the content of harmful substances such as ammonia nitrogen and nitrite in the water to provide a good wintering environment for the fish. Sulfate Series,Feed Grade Magnesium Sulfate,High Purity Medicine Grade,Magnesium Sulfate Dried Powder LIANYUNGANGLONGTAIWEI FOOD INGREDIENTS CO.,LTD. , https://www.longtaiweifood.com
Four measures for increasing the weight of fish during wintering