In recent years, the shrimp aquaculture industry in China has recovered, and the shrimp aquaculture production in Guangdong, Guangxi, and Hainan has increased. In particular, the shrimp aquaculture industry in Hainan began to develop rapidly in 1997. It mainly promoted the cultivation mode of high-level pools of prawn and the technology of healthy shrimp cultivating in low-level pools. The water surface of high-level ponds developed from nearly 100 acres at the beginning of 1997 to 1999. Nearly ten thousand mu of land, and 7 million mu of shrimp in the low position. With the development of the shrimp industry, the disease of shrimp has become more and more serious. The incidence rate in Hainan is 60%-70%. Based on our investigations and practices in the past two years, we have proposed the following exploratory opinions on the prevention and control of fulminant diseases of Penaeus monodon. First, the incentive analysis (a) external factors 1. The sea environment is contaminated, due to blind pursuit of high yields in some areas, the use of high-density farming, so that the shrimp ponds accumulated too much organic matter, a lot of water change and clearing pond scour and silt, without treatment directly Discharged into the sea area, resulting in eutrophication of the sea area, the pathogen shrimp effluent discharge into the sea, but also lead to the spread of shrimp disease. 2. The catastrophic effect of climate change, shrimp peak incidence often occurs after the abnormal flow of cold or continuous storms. The chilling rain in March 1999 and the continuous heavy rain in May caused the onset of fluctuating shrimps in Hainan. Because of the abrupt changes in the regional climate, changes in the environment of near-seawater sources and shrimp ponds, such as changes in salinity, pH, water temperature, dissolved oxygen, and ammonia nitrogen, will affect the ecological balance of shrimp ponds and deteriorate the culture environment. 3. The conditions for shrimp pond culture are not perfect. Contaminated and pathogenic seawater, without treatment, directly divert water and raise shrimp, threatening the risk of disease. 4. The aquaculture technology is not standardized and the management is not perfect; blind pursuit of high output. Excessively high stocking densities, excessive feeding amounts, resulting in excessive shrimp metabolites, deterioration of water quality and sediment quality, coupled with blind drug use, can lead to abrupt changes in the color of shrimp ponds. "Shrimp raises water first," which is the motto of the breeding industry. Shrimp pond water color is not good, water quality indicators are unstable, often induced shrimp disease. (b) Internal factors 1. The strength of the shrimp body constitution. The use of high temperature and frequent use of antibiotics and broodstock shrimps that have been produced in four or five batches of nauplii produce poor disease resistance and are susceptible to disease. 2. Potential risk of shrimps carrying viruses. At present, domestically produced broodstock are few, and many nursery units use imported broodstock that have not been quarantined abroad and may carry viruses. Second, prevention and control measures For fulminant shrimp disease, there is no effective treatment of drugs and methods, prevention-based, it is the fundamental prevention and treatment of shrimp disease. For this purpose, the following preventive measures are taken in accordance with the shrimp disease occurrence factors. 1. Optimizing the external environment of breeding To optimize the external environment is to reduce the breeding of self-pollution of near-seawater sources. The sewage discharged from shrimp rearing ponds can be discharged into the sea after treatment to prevent the virus from infecting the plankton and crustaceans in the seawater, so that when no shrimp ponds are changed, the pathogens are brought back into the ponds and cross infection occurs. . In the first half of 1999, such cross-infections occurred in many farms in Hainan and they became infected with white spot virus disease. For a conditional farm, sandy seawater wells or freshwater wells can be used as well as relatively independent shrimp pond water circulation systems as in Thailand's shrimp farming model. 2. Optimizing the environment within the aquaculture To optimize the internal environment is to improve the ecological environment of shrimp ponds. The most fundamental measures are to reduce the pollution of organic matter and maintain the stability of water quality. Thoroughly dredging and maintaining good bottoms. Scientifically feed high-quality feeds, and scientifically calculate the amount of feed according to the number of shrimps and individual size, minimize the number of baits and increase the utilization rate. With proper addition of a certain amount of seawater or freshwater, the indicators of water quality are constantly monitored to maintain water quality and maintain the ecological balance of shrimp ponds. In order to prevent white spot disease. In the first half of 1999, we appropriately added appropriate amounts of fresh water in the middle and late stages of some shrimp pond tests. During the culture process, gradual reduction of salinity can reduce the infection rate of white spot virus. The test shrimp grew well and white spot virus did not occur until harvest. 3. Strengthen quarantine Before purchasing shrimp seedlings, quarantine the shrimp seedlings and confirm that they do not carry the virus before purchasing. 4. Use drugs with caution. Symptomatic remedy has the effect of preventing and curing disease, but some drugs that use excessive frequency can pollute the environment and make the pathogen resistant to drugs. Therefore, it is necessary to understand the drug properties and effective dosage. Appropriate use of environmental protection agents in the breeding process. Dolomite powder acts as a buffer. Stabilize water quality, increase calcium ions, etc.; for example, zeolite powders mainly decompose organic matter and improve the quality of bottoms. 5. Increase the immunity of shrimp. Many experts have shown that polydextrose stimulates the immune system of shrimp and activates its immunity to achieve a disease-resistant effect. We add a certain amount of polysaccharide drugs to the feed, and pay attention to feeding high-quality full-price nutritional feed to improve the body composition of the shrimp, such as adding 1-2 grams of vitamins and trace elements per kilogram of feed to supplement the nutrition of shrimp. Need to enhance physical fitness and improve immunity. 6. Strictly implement the disease shrimp pond isolation system. The outbreak of viral diseases in Hainan in the second half of 1998 and the first half of 1999 was mainly due to lax isolation. Pathogens spread through cross-breeding organisms such as crabs, mice, and waterbirds, causing cross-infection. Therefore, shrimp ponds that have been infected with viral diseases should be treated in time or strictly isolated to prevent cross-infection. How to control the growth of moss in the shrimp pond With the deterioration of marine pollution, the eutrophication of seawater in the sea area has resulted in a large number of mosquito breeding in shrimp ponds in recent years. This has severely affected shrimp pond aquaculture. Through several years of production practices, the author has taken some countermeasures and achieved relatively good results in controlling moss growth. The shrimp culture model adopted by us is based on the ecological healthy breeding mode of shellfish, rare shrimp, and fish and crab. Moss in the shrimp pond in a large number of breeding, the main hazards are: 1. Serious consumption of inorganic salts in the water, so that the normal metabolism of nutrients in shrimp ponds were destroyed, the water quality became lean. Shellfish mixed with shellfish are mainly fed benthic algae and organic debris. The water quality is lean, shellfish have no food, affect the growth of shellfish. 2. Moss will cover a lot with mud coating. The bottom cultured shellfish will suffocate and die. Other cultured fish, shrimps, crabs, and other products will be affected by the worms and die, reducing the survival rate. 3. With the increase of water temperature and temperature, the moss is thrown up in the pool. It is blown by the wind to the corner of the pool or darkens at the bottom of the pond, giving off a bad odor. In the process of decomposition, it produces toxic gases such as hydrogen sulfide, which increases the ammonia nitrogen content in the pool, reduces the dissolved oxygen content in the water, and can cause poisoning and anoxic death in aquatic products. After the moss is produced, some drugs can be used to kill the moss, but it is easy to cause harm to other cultured species and produce side effects. Generally, it is not appropriate to use drug removal. We took some measures in the early stage of cultivation and during the breeding process to effectively control the growth of moss in the shrimp pond. 1. After the catch of the winter cultured species is finished, drain the pool water and do not accumulate water in the pool and expose it to freezing, and use lime to disperse it in an amount of 10-20 kg per mu. 2. The base of the shrimp pond should be smooth, without mud, remove impurities, firewood, and reduce the chance of moss growth. 3. Before the shrimp ponds were cultured, the water was soaked in the pond and discharged several times in advance. The seawater was filled again, and 20 ppm of tea seed cake was used for clearing the pond to kill harmful fish impurities without any discharge. After the tea seed cake is applied, the transparency of the pool water is reduced, and the algae species can be rapidly propagated. The effect of the fertilizer and water on culturing the algae can inhibit the growth and germination of the moss. After one week, the toxicity of the tea seed cake will disappear. Afterwards, the stocking of the seedlings can be carried out with water and no water loss. In the early stage of aquaculture, the change of water color can be seen, and additional fertilizer or water exchange can be used to adjust the pool water so that the algae in the pool can reach a certain density. This will not only cause moss to occur, but also promote the healthy growth of fish, shrimp, and crab shells. The effect is ideal. 4. Using a motor boat driving method, the motor boat runs in the pond to produce turbid waves, which make the pond water become paralyzed and reduce the transparency of the pool water to inhibit the growth of moss. And the water waves can roll up the moss and roll it to the ditch for removal. 5. The use of artificial removal methods. The two people curled up with bamboo poles and curled up with moss. Can also be used special moss and net fishing or draining water can be removed. 6. After a large number of mosses are rotted and rotted, causing pollution to the sediment, they should be replaced with water or photosynthetic bacteria (5 kg/mu), applied once every two months, or the bottoms should be disinfected with quicklime. The ridge-tailed white shrimp is a kind of important economic shrimp that is unique to China. It is delicious and nutritious. It can be processed into dried products in addition to fresh food. In the autumn and winter of shrimp ponds, white-tailed shrimps are cultured, that is, after the second-long-tailed shrimps are harvested, white-seedlings are harvested from the seedlings or broodstock by self-cultivation and raised to live for sale before and after the Spring Festival. With the characteristics of low cost, short cycle, easy management, and high profitability, in recent years, this method has been commonly used in the county's postal stations and snake-distribution shrimp ponds, and good results have been achieved. The yield is as high as 30 kilograms, and the benefits are very high. 1500 yuan. White shrimp breeding in autumn and winter is conducive to improving the utilization of shrimp ponds, so that the winter shrimp ponds can fully play the benefits. It is worth promoting everywhere. First, the biological characteristics of white-tailed shrimp 1. habitat habits. The white-tailed white shrimp lives in the shallow sea near the shore and has strong adaptability to the environment. The suitable temperature range is 2°C to 39°C, and the water temperature can also survive at -3°C; the salinity range of 3.87‰ to 30‰ can adapt to the salty condition. The fastest growing in fresh water. Poor tolerance to hypoxia, less than 1mg/L, will die due to lack of oxygen. 2. Diet and growth. The tail-tailed white shrimp has a wide range of dietary habits and can feed on both animal and plant foods, but especially eats fresh fish, shrimp, and shellfish. The growth cycle is short, 2-3 months can grow into commercial shrimp. 3. Breeding habits. The white-tailed white prawn has a high fertility, and it is almost always held egg-bearing shrimp. Breeding period generally occurs in the spring, summer and autumn, about 10 times a year. Second, the ridge tail shrimp shrimp pond culture technology 1. Shrimp pond conditions. General shrimp ponds can be cultured, but especially in the bottom of the harbor, the sea water salinity is low, and shrimp ponds rich in natural white shrimp resources in the nearby sea area are the best. 2. Leave white shrimp seedlings. Different methods can be adopted according to different situations. (1) When the long-haired shrimp is harvested from the late July to the middle of August in the lunar calendar, white-shrimp seedlings should not be more than 2 cm in length. It is important to keep the white-shrimp seedlings in the pond. When shrimps are generally placed, the long-haired shrimps first exit, and finally a large number of white shrimps are hatched. This time, they must close the gates in time and repeatedly put the shrimps. The shrimps can be put to the end and the white shrimps can be kept. The shrimp seedlings; (2) pay close attention to the occurrence of white shrimp seedlings in the sea area. When the last time the shrimp seedlings emerged, they adopted the means of draining the nets and water-dense nets to incorporate the white shrimp seedlings. (3) Adopt the method of breeding white shrimp seedlings with fertilizer to increase the density of shrimp seedlings in ponds. After the last batch of white shrimps in the pond held the eggs in early August, they stopped entering and draining water, and increased the density of algae in the pond through fertilizing the baits, so that the white shrimps had sufficient feed after hatching, which greatly improved the survival rate of the shrimp seedlings. If there are not enough eggs in the pond, they can be caught from the sea. Generally 150-200 acres per mu. The combination of the above three methods can achieve better results. 3. Feed the bait. Adhere to feeding every day, shrimp can be used with food, fresh shrimp material, also available wheat bran, No. 4 powder, etc., depending on the density of shrimp in the pond, the size of the shrimp and eating conditions determine the amount of feeding. In the early period, it gradually increased in the middle period, and later, as the water temperature decreased, the amount of feeding was reduced or basically not cast. Generally, 0.5-1 kg of dry bait is fed per acre, and the water temperature in winter falls below 5° C. White shrimp are no longer eating, and feeding is stopped at this time. 4. Clear the enemy. Due to the unfinished ponds after the capture of the second pupae of long-haired shrimp, and naming seedlings are inevitably brought into the enemy's harmful organisms, it is necessary to use 15ppm tea cake cakes in the early stage of the cultivation to harm the animals. 5. Water quality management. Every time there is a large tide, the water will enter and drain once and change the water volume by 10-20% so as to promote the peeling of white shrimp. If the water quality in the pond is poor, the amount of water should be increased. 6. patrol pond inspection. The patrol pond should pay attention to observation of shrimp feeding, growth, water color, embankments, inlet and outlet gates, gate nets, etc., and encounter adverse weather conditions. In particular, it is necessary to observe and take timely measures to ensure the safety of shrimp ponds and the healthy growth of white shrimp. 7. Collect in time. Before and after the Spring Festival, the body length of white shrimp has grown to 5-6cm, and the market price is the highest. It can be listed and sold fresh.
Electronic Cigarette Accessaries
Electronic Cigarette Accessories of Various of products, including Mechanical Mod Tube series, Vape series and Drip tip, provide product pictures and basic parameters, we are committed to supply chain management, we are a professional Chinese manufacturer of Mechanical Mods Kit and we are looking forward to your cooperation.
Electronic Cigarette Accessaries
Electronic Cigarette Accessories,Electronic Cigarette Vape,Electronic Cigarette Drip Tip,Mechanical Mod Tube,Vape E Cig
Dongguan Marvec Electronic Technology Co.,Ltd , http://www.marvec-cn.com