What should be noticed in the freshwater culture of Penaeus vannamei
2018-06-20 05:01:40
In 2001, the freshwater pond of Yingkou Town, Yingkou City was used to test the success of 37 mu of South American white prawn, with an average yield of 276 kilograms per mu, an output value of 9,977 yuan per mu, and a profit of 5,918 yuan per mu, which achieved good economic and social benefits. It has been proved that Penaeus vannamei is an excellent variety suitable for freshwater aquaculture in coastal low-lying saline-alkali and semi-humid areas in our province.
First, the environmental requirements
1. Water temperature: Penaeus vannamei is a tropical shrimp that is not tolerant of low temperatures at high temperatures. The water temperature for survival is 6-40°C, the growth water temperature is 15-38°C, and the suitable water temperature is 23-34°C. When the water temperature is lower than 15°C, feeding is affected, and it begins to die below 6°C.
2. Salinity: Penaeus vannamei is a broad-saline shrimp with a salinity range of 5 ‰-40 ‰ and an optimum of 10 ‰-25 ‰. In the case of gradual desalination, the salinity can also be 0-2 ç›. Bred in fresh water.
3. pH: PH: Adaptable range 8.00.3, PH value less than 7, higher than 9.2, activity is restricted.
4. Dissolved oxygen: The ability to resist hypoxia is outstanding. The minimum tolerable capacity is 1.2 mg/l. In the breeding process, it is generally required that the dissolved oxygen is greater than 4.0 mg/l and not less than 2.0 mg/l.
5. Shrimp pond transparency: about 30 cm in the early stage and 40 cm in the later stage. The low transparency in the shrimp ponds suggests that there are many plankton in the shrimp ponds. These plankton can be used as food for Penaeus vannamei.
6. Water color: yellow-green or yellow-brown, which is the color of plankton in the water for a long time.
Second, stocking preparation
1. Qingchi: The area of ​​the shrimp pond is the best 5 to 20 mu, the depth of water is 1 to 1.5 meters, and it cannot exceed 2 meters. The clear pond should be thorough, and no water grass or wild fish can be left.
Clear pool can use dry and wet methods. After the dry season, the fish or shrimp in the pond is used. After the fish or shrimp is evacuated, the pool water is drained. The bulldozer is used to remove the sludge from the bottom of the pond. It is advisable to see the original soil and then dry it. The wet method is repeated flushing with a mud pump, and the slurry is pumped out of the pond and then dried.
2. Disinfection at the bottom of the pool: It should also include inflow ditches and dam slopes. Generally used lime (block ash) 100-150 kg per mu.
3. Influent salinity adjustment: According to the amount of salt in the water source, the salinity can be adjusted to about 15‰-20‰ or 5‰. The pure freshwater shrimp pond can be adjusted to more than 3‰, which will greatly improve the survival rate of the cultivation. rate.
4. Water disinfection: Disinfect with bleach, 20 grams per cubic meter of water.
5. Fertilizer: should be carried out as early as 7-10 days before the release of seedlings, which is conducive to the large-scale breeding of basic food, and should be carried out at least 7-10 days before seedling release. The organic manure and fertilizer method is: 1 200-300 kilograms of fully fermented pig manure per acre. 2 10 kg of chicken manure per acre plus 4 kg of photosynthetic bacteria and mix well after the fermentation Quanchiposa. 3 Put the chicken feces that have been fermented under high temperature into the pool water. After the water color and transparency have been achieved, remove the mesh bags. Inorganic fertilizer and fertilizer methods are: 1 kg of urea per acre, 0.5 kg of phosphate fertilizer, dissolved in water Quanchiposa. If there is no change in the water color within 5-6 days, it is necessary to introduce and carry out the second fertilizer. Drug fertilizer water method: with fertilizer, biological fertilizer and water. Follow the instructions. In addition, photosynthetic bacteria and EM bacteria should also be properly applied to achieve the purpose of adjusting the pH and degrading harmful substances such as ammonia nitrogen and hydrogen sulfide.
Third, seed selection and stocking
1. Selection of shrimp seedlings: After strict treatment of shrimp seedlings, the treatment time is required to be more than 7 days, the salinity difference does not exceed 2 ‰, the temperature difference does not exceed 5°C, and the size is generally more than 1 cm. The appearance is robust, the exercise is flexible, and the whole body is free. Disease, no specific pathogen.
2. Shrimp stocking: The stocking time of our province should be chosen from June 1 to June 10, when the water temperature is above 18°C. 1 test water: 2-3 days before stocking shrimp should be tested first to see if the pool water is suitable for the growth of shrimp. 2 After stocking first, stocking: In the corner of the shrimp pond, fence material (40 mesh net, nylon membrane, color strip cloth) is enclosed into a holding pool, and the holding pond area is designed according to 1,000 tails/square meter. After the shrimps are shipped back, they can raise them in the holding pool for 10-15 days before allowing them to swim to the rearing pool. If it is not conditional, it is also possible not to raise the stock and directly put the shrimp in the pool.
3. Putting seedlings density: 10,000 to 15,000 tails per acre for coarse farming, about 100 kilograms per mu, semi-extensive farming, 30,000 tails per mu, about 200 kg per mu, 50,000 to 60,000 tails per mu 400-500 kilograms per mu. The shrimp ponds with good conditions are cultured at a density of 80,000 to 100,000 per acre, and factory-raised acreage of 200,000 to 500,000 shrimps per mu.
First, the environmental requirements
1. Water temperature: Penaeus vannamei is a tropical shrimp that is not tolerant of low temperatures at high temperatures. The water temperature for survival is 6-40°C, the growth water temperature is 15-38°C, and the suitable water temperature is 23-34°C. When the water temperature is lower than 15°C, feeding is affected, and it begins to die below 6°C.
2. Salinity: Penaeus vannamei is a broad-saline shrimp with a salinity range of 5 ‰-40 ‰ and an optimum of 10 ‰-25 ‰. In the case of gradual desalination, the salinity can also be 0-2 ç›. Bred in fresh water.
3. pH: PH: Adaptable range 8.00.3, PH value less than 7, higher than 9.2, activity is restricted.
4. Dissolved oxygen: The ability to resist hypoxia is outstanding. The minimum tolerable capacity is 1.2 mg/l. In the breeding process, it is generally required that the dissolved oxygen is greater than 4.0 mg/l and not less than 2.0 mg/l.
5. Shrimp pond transparency: about 30 cm in the early stage and 40 cm in the later stage. The low transparency in the shrimp ponds suggests that there are many plankton in the shrimp ponds. These plankton can be used as food for Penaeus vannamei.
6. Water color: yellow-green or yellow-brown, which is the color of plankton in the water for a long time.
Second, stocking preparation
1. Qingchi: The area of ​​the shrimp pond is the best 5 to 20 mu, the depth of water is 1 to 1.5 meters, and it cannot exceed 2 meters. The clear pond should be thorough, and no water grass or wild fish can be left.
Clear pool can use dry and wet methods. After the dry season, the fish or shrimp in the pond is used. After the fish or shrimp is evacuated, the pool water is drained. The bulldozer is used to remove the sludge from the bottom of the pond. It is advisable to see the original soil and then dry it. The wet method is repeated flushing with a mud pump, and the slurry is pumped out of the pond and then dried.
2. Disinfection at the bottom of the pool: It should also include inflow ditches and dam slopes. Generally used lime (block ash) 100-150 kg per mu.
3. Influent salinity adjustment: According to the amount of salt in the water source, the salinity can be adjusted to about 15‰-20‰ or 5‰. The pure freshwater shrimp pond can be adjusted to more than 3‰, which will greatly improve the survival rate of the cultivation. rate.
4. Water disinfection: Disinfect with bleach, 20 grams per cubic meter of water.
5. Fertilizer: should be carried out as early as 7-10 days before the release of seedlings, which is conducive to the large-scale breeding of basic food, and should be carried out at least 7-10 days before seedling release. The organic manure and fertilizer method is: 1 200-300 kilograms of fully fermented pig manure per acre. 2 10 kg of chicken manure per acre plus 4 kg of photosynthetic bacteria and mix well after the fermentation Quanchiposa. 3 Put the chicken feces that have been fermented under high temperature into the pool water. After the water color and transparency have been achieved, remove the mesh bags. Inorganic fertilizer and fertilizer methods are: 1 kg of urea per acre, 0.5 kg of phosphate fertilizer, dissolved in water Quanchiposa. If there is no change in the water color within 5-6 days, it is necessary to introduce and carry out the second fertilizer. Drug fertilizer water method: with fertilizer, biological fertilizer and water. Follow the instructions. In addition, photosynthetic bacteria and EM bacteria should also be properly applied to achieve the purpose of adjusting the pH and degrading harmful substances such as ammonia nitrogen and hydrogen sulfide.
Third, seed selection and stocking
1. Selection of shrimp seedlings: After strict treatment of shrimp seedlings, the treatment time is required to be more than 7 days, the salinity difference does not exceed 2 ‰, the temperature difference does not exceed 5°C, and the size is generally more than 1 cm. The appearance is robust, the exercise is flexible, and the whole body is free. Disease, no specific pathogen.
2. Shrimp stocking: The stocking time of our province should be chosen from June 1 to June 10, when the water temperature is above 18°C. 1 test water: 2-3 days before stocking shrimp should be tested first to see if the pool water is suitable for the growth of shrimp. 2 After stocking first, stocking: In the corner of the shrimp pond, fence material (40 mesh net, nylon membrane, color strip cloth) is enclosed into a holding pool, and the holding pond area is designed according to 1,000 tails/square meter. After the shrimps are shipped back, they can raise them in the holding pool for 10-15 days before allowing them to swim to the rearing pool. If it is not conditional, it is also possible not to raise the stock and directly put the shrimp in the pool.
3. Putting seedlings density: 10,000 to 15,000 tails per acre for coarse farming, about 100 kilograms per mu, semi-extensive farming, 30,000 tails per mu, about 200 kg per mu, 50,000 to 60,000 tails per mu 400-500 kilograms per mu. The shrimp ponds with good conditions are cultured at a density of 80,000 to 100,000 per acre, and factory-raised acreage of 200,000 to 500,000 shrimps per mu.
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