What is the healthy aquaculture technology in freshwater ponds?
First, technical points
1. The water quality and environmental water sources are sufficient, and the water quality meets the fishery water quality standards. There is no pollution source, large-scale production activities and noise around the pond.
2. The pond area is 5 ~ 10 mu, and the pond depth is 2 ~ 2.5m.. The bottom of the pond is flat, which is convenient for drying the pond and pulling the net. The silt at the bottom of the pond is about 20 cm thick and has good water retention performance. Water, electricity and roads are connected, and irrigation and drainage are convenient. According to the production needs, each pond is equipped with 3kW aerator and bait feeder.
3 producers with complete production facilities must have water pumps, aerators, baiting machines, oxygen cylinders, nets, fishing nets, fishing and other common production equipment. , and often maintain them to keep them in good working condition.
4. Preparation before stocking Drain the pond in winter or early spring, trim the pond and remove excessive silt. The bottom of the pool is frozen and exposed to the sun, which makes the mud loose, kills germs and reduces diseases. 7 ~ 10 days before stocking fish, dry disinfect each mu with quicklime 100 ~ 150 kg. On the fourth day after disinfection, water was added to the depth of 0.8 ~ 1m, and the lime and sludge were stirred manually or mechanically, so that the nutrients in the sludge were released into the water, and the harmful substances were fully oxidized, so that the water temperature was dried in the sun and increased, achieving the purposes of fertilizing water, sterilizing and purifying water quality, and making preparations for releasing fish.
5. Fish stocking time Fish stocking time should be sooner rather than later, generally completed before late autumn, early winter or late February. Early stocking can make fish adapt to the new living environment as soon as possible and reduce stress reaction. In particular, fish species purchased from other places should be stocked in advance.
6. The fish species are of strong quality, normal body shape, complete scales and fins, healthy body and no epidemic disease. The body color is bright, the body is slippery, there is no trauma, and the traceability is strong. It is best to domesticate fish. Choose fish caught by dragnet, and don't stock fish polluted by sludge in the pond.
7. The specifications and density of fish species are neat, and the same specifications are basically the same, with a general specification of 50 ~ 100g/ tail. Generally, the stocking density is determined according to the following three points: first, determine the breeding type, whether it is polyculture or monoculture; Second, the yield per mu should be controlled within 750 kg; The third is the expected listing specifications.
8. Before disinfection and stocking of fish species, the fish species must be disinfected. Generally, fish species are soaked in 3% ~ 5% salt for 5 ~ 10 minute. Soaking time depends on water temperature, weather and tolerance of fish species.
9. Strictly implement the national standards and relevant technical specifications, and strictly implement the regulations on aquaculture quality and safety management, technical standards for aquatic products, quality standards for germplasm and fry, quality standards for pollution-free aquatic products and technical operation specifications.
10. Establish an emergency system for forecasting aquatic animal and plant diseases. First, the establishment of aquatic animal and plant disease forecasting system, through the quota, fixed point, fixed species forecast, analysis of disease occurrence and epidemic trend, put forward disease control measures; Secondly, after years of disease prediction, it is necessary to train personnel, accumulate data, establish a database and analysis and processing system for disease prediction, gradually establish and improve a disease prediction system and an emergency system, formulate an operational emergency plan for disease prevention and control in this area, and do a good job in disease prevention before the occurrence and spread of diseases, so as to truly make the prediction of aquatic animal and plant diseases serve fisheries and fishermen.
1 1. Daily management
(1) Water quality adjustment Before stocking fish, the water depth should reach about 1 meter. Fish farming with river water should be filtered to prevent wild fish and sundries from entering. From the end of May to the beginning of June, add water to 1.8m, and then gradually fill the pool with the growth of fish. From July to September, it is best to change the water once a month (release the lower water), and the amount of water changed each time is not less than 1/3 of the pool water. Keep the transparency of the pool water at about 30cm, the dissolved oxygen at about 5mg/L, and the pH value at 7 ~ 8.5. Using water measurement technology to adjust aquaculture water quality to adjust water quality.
(2) Rational use of aerator, achieving "three on and two off" and starting at noon on sunny days 1 ~ 2 hours; Turn on the machine at the right time on cloudy days until the floating head is raised; When there is serious danger of floating head due to continuous rain, start the machine before the floating head rises until the floating head rises. Generally, it is closed at night, and it is closed during the day in rainy days. In the peak season of fish growth, it should be started at noon on sunny days, and the pond has a large amount of fish and takes a long time to start, otherwise it will take a short time to start.
(3) Take samples regularly to measure fish growth. From May, the growth of fish was sampled and measured every 10 ~ 15 days. According to the water temperature and weather conditions, the feeding amount was flexibly controlled to prevent the normal growth of fish from being affected by excessive or insufficient feeding.
(4) Insist on patrolling the pond, keep a log of the pond, patrol the pond in the morning and evening in summer and autumn and at night, pay attention to the weather, water quality and fish situation, and take timely measures when finding danger signals to avoid losses. Keep a journal. The main contents of the log include: weather, water temperature, air temperature, feeding amount and times, fish disease prevention and control, start and end time of floating head, start and end time of aerator, charging and discharging time and charging and discharging quantity, etc. Analyze and summarize regularly and adjust management measures in time.
(5) The prevention of fish diseases should adhere to the principle of "prevention first, prevention is more important than treatment", and adhere to the methods of "pond disinfection, food field disinfection, feed disinfection and tool disinfection" to prevent fish diseases regularly and pertinently. Found sick fish, dead fish out in time, dig a pit to bury, to prevent the spread of fish diseases.
Choose fishery drugs produced by enterprises with complete "three certificates" (fishery drug registration certificate, fishery drug production approval certificate and implementation standard number). Scientific diagnosis of fish diseases and correct use of fishery drugs. When using more than two drugs, we should pay attention to the synergistic and antagonistic effects between drugs, and prepare and apply drugs in strict accordance with the operating procedures; Use Chinese herbal medicines and biological agents to prevent and treat fish diseases as much as possible, do not use or use less antibiotics, prohibit the use of illegal fishing drugs, and strictly abide by the withdrawal period. After taking the medicine, carefully observe the reaction and curative effect of the fish, and take measures to solve the problems in time.
When crustaceans such as shrimps and crabs and scaleless aquatic animals such as fish, eel, loach and frog apply drugs, special attention should be paid to the types and methods of application. For example, crustaceans are forbidden to use phosphorus-containing drugs such as trichlorfon.
After the pond is protected by building materials such as cement boards, stones and bricks, the contact between the pond water and the soil on the slope of the pond is cut off, which reduces the adsorption of drugs by the soil, so the dosage of drugs should be reduced appropriately.
When using drugs, it is not necessary to dilute all drugs with water at one time, but dilute them several times according to the size of the water surface, so that the drug concentration is evenly distributed in the pool water. Spray evenly when applying pesticide. After pesticide application, the aerator is turned on to stir the pool water, so that the drug can fully contact with the pool water and be stirred evenly, so as to achieve the purpose of preventing and treating fish diseases.
Carefully record the process of fish disease prevention and control, mainly including the name of fish disease prevention and control, the name of fishery medicine, batch number, production time, manufacturer and administration method (bait feeding, bag hanging, whole pool sprinkling, etc.). ), time, equipment, weather conditions (water temperature, air temperature), application personnel, treatment effect. Compared with the same period of last year and similar ponds nearby, the experience and lessons were summarized, and the rules were found out to provide technical and practical support for the prevention and control of fish diseases.
12. Technology type
(1) beneficial microorganism water quality control technology
① Nitrifying bacteria: it does not need to be activated when used, such as glucose and brown sugar. Can not be used to expand culture, just simply dissolve and sprinkle with pool water. Generally, it takes 4 ~ 5 days to see the obvious effect after adding nitrifying bacteria, so it is a good way to solve this contradiction to advance the time of adding nitrifying bacteria. At the same time, in order to better improve the efficiency of nitrifying bacteria, nitrifying bacteria should be used a few days in advance to avoid fast-growing live bacteria competing for space.
Nitrifying bacteria should not be used together with chemical oxygenators such as sodium percarbonate or calcium peroxide, because the oxygen atoms decomposed by these substances in water will kill nitrifying bacteria. Therefore, before using nitrifying bacteria, the chemical oxygenator should use 1 hour.
The pH value and dissolved oxygen in aquaculture ponds are closely related to the use effect of nitrifying bacteria. The optimum pH range of nitrifying bacteria is 7.8 ~ 8.2, and the dissolved oxygen should be no less than 2 mg/L. ..
② Photosynthetic bacteria: Using photosynthetic bacteria in aquaculture water and adding photosynthetic bacteria to feed can improve water quality, reduce oxygen consumption, promote the growth of fish and shrimp and increase yield. Photosynthetic bacteria should be used when the water temperature is above 20℃, and it is not suitable for low temperature and rainy days. When it is used in a pond, 2-5g of photosynthetic bacteria are mixed with finely divided dry fertilizer and soil powder and sprinkled in a fish pond, and then every 20 days or so, 1-2g of photosynthetic bacteria is mixed with water per cubic meter of water, and then spread all over the pond. Mix 5 ~10g of photosynthetic bacteria with finely divided dry fertilizer soil powder, evenly sprinkle each cubic meter of water into the shrimp pond, then mix 2 ~10g of photosynthetic bacteria with water every 20 days or so, and then spread all over the pond. When it is used to feed fish and shrimp, it is mixed at the ratio of 1%. When it is used for disease control, it can be used continuously, with a water pond 1 ~ 2g and a shrimp pond 5 ~ 10g per cubic meter, and then it is sprinkled all over the pond. When applying manure or chemical fertilizer in ponds, the effect of adding 2 ~ 5g photosynthetic bacteria is more obvious, which can avoid the shortcomings of too much chemical fertilizer and difficult control of water quality, and prevent the deterioration of water quality caused by algae aging.
When the water is thin, it is necessary to apply fertilizer before using photosynthetic bacteria, which is conducive to maintaining the vitality and reproductive advantages of photosynthetic bacteria in water and reducing the use cost. In addition, acidic water is not conducive to the growth of photosynthetic bacteria, so before using photosynthetic bacteria, it is necessary to sprinkle a proper amount of raw lime milk to adjust the pH value of water to about 7.
Drugs can kill the living bacteria of photosynthetic bacteria preparation, so they can't be used with disinfectants at the same time. It takes a week to disinfect the water.
(3) Bacillus: When the bottom environment of aquaculture water is deteriorated and the algae phase is not good, Bacillus should be used as soon as possible. It can quickly utilize macromolecular organic matter, mineralize organic matter into inorganic salts, and provide nutrition for unicellular algae. The photosynthesis of unicellular algae provides oxygen for the oxidation of organic matter, the respiration of microorganisms and the respiration of aquatic animals. This cycle forms a benign ecological cycle, so that the bacteria in the pond can reach a balance, maintain a stable water color and create a good sediment environment. At the same time of overflowing bacteria, we should start the aerator as far as possible, so that it can multiply in the water and quickly form a population advantage.
Activation is a necessary measure before using Bacillus. The activation method is to add pool water and a small amount of brown sugar or honey, soak for 4-5 hours and then spray, which can maximize the utilization efficiency of Bacillus. /index.php？ Agriculture, countryside and farmers. News page. id=2467