Litopenaeus stylirostris belongs to the order Arthropoda, Crustacea, Decapoda, Swimbill, Penaeidae, Shrimp, and Penaeus vannamei. It is a widely salty tropical prawn species, native to the Pacific coast of Latin America. It can be cultivated in the country of origin throughout the year, and is often mixed with white shrimp. It has the advantages of high growth rate, low feed cost, wide temperature tolerance and salt tolerance, low dissolved oxygen resistance, strong disease resistance, and high meat yield. With the continuous improvement of South American blue prawn breeding technology and the acquisition of SPF shrimp, artificial breeding has gradually been promoted. China began to introduce and popularize breeding after 2000, and obtained the success of artificial breeding and breeding. It has now become a new one in China. Cultured shrimp species. I. Breeding pool construction and facilities 1. Each industrialized aquaculture pond has an area of ​​1000?--1500?, water depth of 1.5m-2.0m, and a pool of square-shaped or oval-shaped cement pool is suitable. The bottom of the pool is shaped like a pot, and the middle part is provided with a sewage outlet. The inlet and outlet gates are oppositely set. The address should be selected in the vicinity of the shoreline where the original shrimp culture area is of good quality and the water quality is 1m-2m above the high tide line. Water is piped from the low tide area to the shore reservoir, and then the pool water is allowed to flow into the human aquaculture pond. Because of the high topography and free from the impact of tides, it is convenient for drainage and cleaning, and it is easy to obtain high output and high efficiency. 2. Each breeding greenhouse should be equipped with two disinfection tanks and two water reservoirs, each with an area of ​​about 1 mu and a water depth of more than 2 m. 3. According to the requirements of the scientific management layout, the position of the reservoir and the way of entering and exiting the water should be determined according to local conditions. It is forbidden to stock other species in the reservoir to ensure the quality of the impoundment. 4. According to the design requirements, it is equipped with a waterwheel type aerator. Generally, lkW aerator is equipped with 2 sets per acre area. During the breeding season, in the middle and later stages of the special revival, the oxygen should be turned on without interruption to allow the pool water to flow to one side to form a circulating flow to ensure oxygenation. Second, pre-release preparations The newly-created shrimp pond should be soaked for about half a month before being used, and then the water should be drained off. The culture pond should be cleaned with 250ppm bleach, and prepared: used. 2. The seawater that is taken into the disinfection tank from the open sea is natural seawater, and is disinfected in the disinfecting tank by means of disinfecting with 80 ppm to 100 ppm of bleaching water. After 48 hours of disinfection, the water is injected into the reservoir. 3. Artificially cultivating basic bait organisms in a reservoir by artificially inoculating tanks with diatoms such as diatoms, Platymonas, and fertilizing fertilizers, generally in the amount of 1 ppm-2 ppm of ammonium bicarbonate and 0.1 ppm of superphosphate. -O. Fertilize at a rate of 2ppm, fertilize once every other day, and stop fertilizing in rainy weather. During this period, the water color is preferably light yellowish brown or yellowish green, and the transparency is appropriate around 40cm. Two disinfection tanks and reservoirs are used alternately to achieve the desired water treatment effect. Third, shrimp seedling selection, holding and stocking The selection of strong, non-invasive and virus-free shrimps is the key to ensuring the success of breeding. Untested shrimp should not be blindly stocked. 2. The size of the shrimp out of the pond reaches 6mm-8mm, and the water temperature in the breeding pond can reach above 20°C, and it can be directly cultivated, and can also be cultivated after intermediate holding. The holding pool can be formed by using a 40-mesh sieve net in the corner of the rearing pond. After the shrimp body reaches 2 cm-3 cm in length, the seine net is removed and the cultivation period begins. 3. The seedling density should be determined according to the planned yield and different farming conditions. If the shrimp is planned to produce 2000kg-4000kg per acre, it is generally worth stocking 200/400 pigs per square meter; it can also be increased or decreased according to the circumstances, and it can be flexibly controlled to achieve the purpose of increasing production and efficiency. 4. Although P. vannamei has a wide range of suitable temperature and salt tolerance, its ability to adapt to temperature and salinity mutations at the seedling stage is poor. Therefore, it is necessary to adjust the water temperature and salinity of aquaculture ponds in advance so that nursery ponds can be adapted to the conditions of holding ponds or aquaculture ponds. When the seedlings are released, the temperature difference cannot exceed 5°C. It is best to control within 2°C. The difference in salinity cannot be greater than 5‰. If it is cultivated with low salinity, the difference in salinity cannot exceed 2‰. Fourth, the development period management During the water environment management and cultivation period, the physical and chemical factors and biological factors of pool water and sediment should be monitored regularly, and indicators with rapid changes should be monitored daily. During the growing period, the standard water quality monitoring standard is the optimum water temperature of 24°C-32°C, and the gradient range of 15°C-34°C can also be grown; the optimum salinity is 15 ‰-37 ‰, and the gradual change range of 5 ‰ -50 ‰ can grow well; The optimum pH value is 7.6-8.3. It can also grow in the range of 7.3-8.6; dissolved oxygen is not less than 3mg/L; ammonia nitrogen is less than 0.2mg/L; More than 0.1mg/L; the organic content of the pool bottom surface does not exceed 5mg/L; the transparency is 30cm-40cm, the color of the water should be determined according to the difference of the biological advantage population, the ideal water color is generally light brown with diatoms, green The pale green color dominated by algae, and the combined effects of the two are reflected in shades of yellow-green. 2. Pre-cultivation (before 6cm in body length) It is the core of management to cultivate basic food organisms and keep the bio-communities in the pool relatively stable. Therefore, new water should be added in time according to changes in water color and biomass to maintain the density of the basic bait organisms. 3. Mid-term (6cm-10cm) As the water temperature rises and feeds increase, organic matter in the water increases, and phytoplankton thrives. Some zooplankton and protozoa that can't feed on the shrimp have the opportunity to flood, which seriously consumes dissolved oxygen in the pool. . at this time,. Clearing ponds should be discharged in a timely manner, and sewage discharge is generally conducted 2 to 3 times a week. At the same time, a small amount of non-polluting, filtered water or organisms that feed on organic detritus can be put into the aquaculture ponds, such as short-twisted, blue-crested, duck-bone quail, quail, etc., of bivalve molluscs, and the food is mild and floating. Bio-food small fish, such as squid, barracuda, squid, etc., in order to achieve the purpose of improving water quality. After heavy rainstorms, the freshwater layer on the surface of the disinfection pool and the livestock pond should be drained in time, and the zeolite powder should be thrown into the pool to stabilize the water quality. 4. In the late growing period (10 cm or more in length) During this period, the shrimps are in a period of rapid growth, and it is difficult to manage water quality. First, to increase the amount of water to be changed, a normal flow method should be adopted, and the daily water exchange volume should be more than 50%. Second, the aerator must be continuously activated. The third is to put water protection agents directly into the aquaculture pond every two weeks; The sewage is discharged once a day to ensure that the bottom of the pool is clean. 5. In the early feeding stage, the basic food in the pond is rich in organisms, which can be fed or fed in small amounts; along with the consumption of basic food organisms, the amount of feeding is gradually increased, and the feed must be selected with high-quality artificial compound feed to strictly ensure the quality; The peak incidence has passed and is close to the collection period of shrimp. It can feed some fresh and live feed without pollution, which will help promote the rapid growth of shrimp and reduce the cost of feed. The shrimp's satiety rate is generally controlled at 70%-80%. 6. Disease prevention and control of blue shrimp in South America has a strong resistance to disease, the entire incubation period is only about 3 months, as long as the preventive measures are appropriate, it is entirely possible to spend safety. However, when the environment is not suitable, the disease can also be caused by infection. The prevention and treatment of diseases must still adhere to the principle of prevention, prevention and control, and strictly control all aspects. Viral diseases are mainly manifested in the stomach of shrimp without food, inactive shrimps, and obvious white spots on the cephalothorax. Currently, there are no effective treatment measures, and comprehensive prevention and treatment should be adopted. The etiology of bacterial diseases is mainly bacterial infections, especially Vibrio infections are more common. The treatment methods are generally to change the environmental conditions, external disinfectants, oral administration of antibiotics, antibiotics and so on. Nutritional diseases are mainly caused by inadequate nutrition, which is mainly manifested in slow growth of shrimps, individual thinness, etc. The treatment method is to identify the reasons for the lack of nutrition and to strengthen the feeding of high-quality feed. In addition, protozoan diseases, algal toxic diseases, and environmental diseases may also occur. Early detection and early treatment should be performed to ensure the smooth development of factory culture.
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