Summer temperatures are high, and aquaculture management should be strengthened.
In hot summer, the sun is hot. In July and August, it is the highest season for temperature and water temperature, and it is also a season for the growth of aquatic animals such as farmed fish and shrimps, crabs and clams. At the same time, it is also a time when the disease has spread and spread, which is the focus and difficulty of aquaculture management. At this time, the quality of feeding and management will directly affect the level of annual output and economic efficiency. In order to ensure the healthy growth of aquaculture and the safety of the summer season, so as to achieve the purpose of stable production and high yield, according to the characteristics of climate and aquaculture production in July-August, the farmers should be reminded that they should do the following management work and precautions.
I. Freshwater conventional fish culture
1,7-8 months is an important period for the cultivation and stocking of conventional fish seedlings. Therefore, summer and fish breeding should be done in July-August. Before the stocking, the seedlings should be sterilized in a timely manner. When stocking, they must be sterilized with salt water or potassium permanganate to prevent bacterial infection. To purchase seedlings from other places, it is necessary to carry out disease detection and quarantine so as not to bring in pathogens.
2. Adult fish breeding management: (1) 7-8 months is the peak season for fish growth. Fertilization and feeding should be strengthened. Ponds with mainly fish and fish should be topdressed according to their color and transparency. Ponds or cages, which mainly eat fish, should be fed in a timely manner. And do feed "four set" (quality, quantitative, positioning, timing), fertilization, "four look" (see fish, see the sky, see the water, see the season); (2) pay attention to water quality control. According to the weather changes in time to increase oxygen and water. Due to the rapid growth of fish in July-August, the amount of food consumed increased, excretion increased, and the water quality deteriorated, resulting in lack of oxygen. Therefore, aerobic machine oxygenation should be started every day. In case of hot weather, it is necessary to extend the time for starting oxygen. At the same time, it is necessary to frequently add new water, raise the water level to more than 1.5 meters, and replace some of the bottom water properly. Promote the use of beneficial microbial agents to improve water quality and sediment quality. During high temperature, it is best to apply once every 15 days microbial agents such as photosynthetic bacteria or em bacteria; (3) to prevent disease. In July and August, the temperature is relatively high, but the water temperature is relatively suitable, and various pathogens in the water are prone to breeding and breeding. This is the season in which fish are susceptible to disease. If ignorance of prevention can easily induce fish disease. In July and August, major diseases that are prone to be outbreaks and epidemics are bacterial hemorrhagic disease, gill disease, enteritis disease, angiosclerosis, Chinese sturgeon disease, and ringworm disease. The focus should be on prevention of bacterial bleeding and parasitic diseases. Regular use of lime, chlorine dioxide, dibromohydantoin, and insecticides and other fishery drugs spilled and disinfected. (4) Strengthen day-to-day management and stick to duty on duty. From July to August, the weather is changeable, and thunderstorms and typhoon weather are prone to occur. Attention should be paid to observing the feeding conditions of fish and oxygen-depleted floating heads. It is found that the signs of hypoxia should be filled with new water and an aerator in time to avoid fish ponds. .
Second, crustacean farming
1. Macrobrachium rosenbergii breeding: The seedlings have been stocked from May to July and have been for more than 2 months. The pond's internal memory density, feeding amount, and oxygen consumption have all increased significantly. Aquaculture management has entered a critical stage. (1) In normal weather conditions, feed as much as possible to feed the shrimp. In particular, we must invest enough to feed the morning and evening feeds, and feeds must be high quality fresh and not bad; (2) turn on oxygen at the right time. Due to the fact that Macrobrachium is in the growing season from July to August, the water temperature and temperature are relatively high. Special attention should be paid to the changes of dissolved oxygen in shrimp ponds to prevent oxygen deprivation. Therefore, oxygenation of aerators should be started in time according to the weather and water quality. The key to opening an aerator is: open at noon on sunny days, open in the wee hours of cloudy days and showers at midnight; (3) Regulation of water quality is an important part of feeding and management. Appropriate increase in the number of shrimp pond flushing can not only improve the water environment, but also stimulate the shellfish growth. Generally flush the water once every 7-8 days, each time increasing the water depth by 10-15cm, and require the flow of water; (4) Rational application of biological agents. In high-temperature weather, it is best to use a combination of microbiological preparations such as eprotocol once every 15-20 days, which can effectively improve water quality and promote the rapid growth of macrobrachium, and can prevent the occurrence of various shrimp diseases.
2. South American White Shrimp Culture: During the period from July to August, it is the peak period for the growth of Penaeus vannamei. At this time, the water temperature is high, the shrimp grows fast, the food intake is large, the excrement is large, the water quality is easily deteriorated, and it easily leads to the pan pool, and at the same time it is a disease. High growth period. Therefore, in order to ensure the healthy and safe growth of Penaeus vannamei, it is necessary to strengthen the feeding management. (1) Strengthen water quality control. Adhere to daily morning and mid-day oxygen boost for 2-3 hours. If you encounter low pressure and hot weather, you should extend the boot time. At the same time, according to the changes in water quality, it is time to change new water, change the water in a small number of ways, replace 1/3 of the pool water every 7-8 days, and then raise the water level appropriately and keep it above 1.8 meters. In addition, due to the large amount of feed in the pond, the amount of excretion in the pool, the increase in water pollution, and the increase in water color, zeolite powder should be applied irregularly to control the water color. Difficult to change the water of shrimp ponds, em bacteria or Bacillus and nitrifying bacteria can be used to improve water quality, splash twice a month, can effectively decompose the pool of organic matter, reduce the concentration of ammonia in water and nitrite. (2) Strictly control the amount of feeding. Feeding should be distributed feeding, small amount of meal feeding method. Feed 3-4 times a day, 70-80% in the morning and evening and 20-30% in the daytime. Daily feeding should be based on weather, water quality, health and activity of shrimp, etc.; (3) Disease prevention. The main preventive measures for the months of July and August are the regular disinfection of water bodies, which are usually disinfected 15-20 days. Disinfectant drugs include quaternary ammonium iodide, bromochlorohydantoin, dibromohydantoin, em bacteria, and nitrifying bacteria. At the same time, vitamins such as vitamin c, immune polysaccharides, and viral proteins should be added to the feed regularly to enhance the body's resistance to disease. At this time, the main diseases of white shrimp are red body disease (peach disease), white spot disease, black shank disease, red leg disease and nitrite poisoning disease. Among them, red body disease, white spot disease, and nitrite poisoning are relatively prominent. Therefore, according to different diseases, it should be correctly diagnosed and controlled in time to prevent the spread of the epidemic; (4) timely fishing, arresting and rearing. At this time, the shrimp grows quickly and the amount of shrimp in the pond is too high. During the aquaculture process, the shrimp should be caught in time to keep large and small, and the shrimp of commercial specifications will be caught and listed to maintain a reasonable shrimp density and promote the growth of the shrimp.
3, crab farming: July-August hot weather, higher water temperature, is the key season for crab farming. At this time, we should strengthen management, carefully rearing, ensure crabs are safe and improve the survival rate of culture. At this point should pay attention to the following points: (1) there is a sufficient supply of aquatic plants. The water surface should be stocked with some water peanuts, leeks, etc. to shade the plants, or pre-plant some emergent plants such as reeds and white water. In the crab pool, a large number of young plants, such as black algae and Vallisneria, should be kept in order to feed the crabs and avoid predators; (2) to ensure clean water. Always check the water quality, change new water frequently, and remove remaining food and dirt in time. The pool water depth should be maintained at more than 1 meter to prevent hot water from burning the crab body and affecting the growth; (3) Pay attention to the feeding of the bait. During the high temperature stage, the proportion of plant food should be increased. Such as wheat, pumpkin, cakes and other crabs are the favorite vegetable feed. Feed these pellets into granules or lumps and place them on the food table to feed the crabs; (4) Prevent disease. The major diseases in this season include trembling disease, scrofula syndrome, and fixed ciliate disease. We must adhere to the principle of ecological prevention and disease prevention, supplemented by drugs and disease prevention. Disinfection usually takes lime, bromochlorohydantoin, etc., or regular use of microorganisms and other beneficial microorganisms to maintain the microecological balance in the crab pool.
Third, turtle management
1,7-8 months is the season for the breeding of Chinese sturgeon in our province, there will be a large number of juveniles hatched. First, we must promptly do a good job of incubation and collection. Second, we must strengthen the intensive cultivation and disease prevention measures. Before entering the pool, the juvenile must be disinfected with potassium permanganate and salt to prevent infection. Actively promote the raising of households for self-breeding and self-cultivation. If you purchase quail eggs or larvae in other places, you should strengthen inspection and quarantine, and conduct strict disinfection to prevent the introduction of pathogens.
2. For turtles raised in greenhouses, due to the high indoor temperature, ventilation and ventilation should be taken into account, and the adjustment of water quality and the reasonable feeding of feed should be strengthened. When moving from the greenhouse to the outer pond for aquaculture, care should be taken that the temperature difference should not be too large, and it is best to choose cool weather in the morning when moving, and to minimize damage and mutual bite when operating, so as to avoid attack after entering the pool.
3. Do a good job of preventing diseases. During the period of 7-8 months, the most prone diseases of the turtle are carrionosis, perforation, white floor disease, mumps and acne, and preventive measures should be taken actively. (1) The greenhouse raising pond should pay attention to the improvement of water quality, regular disinfection, timely changing of water, adding em primordium or immune polysaccharides to the feed to enhance the disease resistance of the carcass; (2) quality control of good seedlings. Farmed turtles are required to purchase a healthy, disease-free species. Prior to stocking into the pool must be strictly disinfected with drugs; (3) regular water quality regulation and water disinfection. Normally use chlorine dioxide, bromochlorohydantoin, EM, and other environmental drugs to alternately disinfect every 20-25 days; (4) Add vitamin C, allicin, and immune polysaccharides regularly to enhance the body's immune system. force.