Pond shrimp crab fish polyculture technology
(1) Pond condition 1. The pond is full of water, no pollution, and the water injection and drainage system is separated; the bottom soil is in loam, no leakage, and the sludge thickness is less than 10 cm; the suitable pH of the pool water is 7 to 8.5, and the dissolved oxygen is 2 mg. / l or more. In general, each pond is suitable for about 3 to 10 mu. The depth of the pool is 1.5 to 2 meters, and the slope ratio is 1:3. The rectangle is rectangular, and the aspect ratio is about 2:1. 2. In the pond, plants such as Hydrilla verticillata and Malay Oozi can be planted, and the area is about 60% of the pond area. In the center of the pond, water, hyacinth and other platforms are used for concealment. The area accounts for 15% to 20 of the pond. %about. Aquatic plants are conducive to the concealment of shrimps and crabs, but also provide some of the plant food; the bottom of the pool can be added shrimp, shrimp balls, cages and other shrimp. 3. Add anti-escape facilities As the crabs have escape habits, therefore, around the pool shore, use a thick plastic film to be laid, and use a thin bamboo basket as a support for hanging around 1 meter away. The membrane is buried in the soil on one side; you can also use calcium plastic plates. Or the surface of the hard plastic board and other smooth materials to erect, but pay attention to keep the interface smooth, avoid crabs over. Anti-escape wall is 0.5 meters high. (II) Stocking 1. Pond clearing Before the stocking, the pond must be dredged and disinfected to kill pathogens such as wild fish, bacteria and parasites. Lime clear pond is generally used. 100 ~ 125 kg per mu, with clear pond should increase the amount of water. 2. Miaoyuan and stocking time The selection of the Yangtze River water crab species is good, requiring the specifications to be neat, robust, moist and physically complete. Green shrimp is better with local varieties. General crab species and earthworms can be stocked in the winter or early spring, and shrimp should be raised at the end of May or early June, which is more economical. 3, specifications and density of shrimp: generally put 1 to 2 kg / mu, so that their own production of shrimp. Crabs: The specifications are 200/kg and 400~600/mu. In addition, 800 to 100 tail fish of large size can be stocked with 800 to 100 tails per acre. 4. It is required that when the crabs are stocked, the water depth should be about 1 meter, and about 300 to 500 kg/mu of organic fertilizer should be applied before stocking for about 10 days to cultivate plankton so that the crab species can ingest enough natural food. At the same time, we must maintain good water quality with a transparency of about 30 centimeters. After June, organic fertilizers should be applied on a regular basis according to the color of water and the number of shrimps. (III) Daily management 1. Feeding Since river crab species are stocked in winter and spring, when the water temperature reaches 10°C in March to April, they start feeding. For crabs, from March to April, the water temperature is lower, the individuals are smaller, the food intake is small, and the cake-like pancakes, pig blood clots, etc. can be fed less; after the water temperature rises in May-June, the individual's food intake is enhanced and fed. The quantity also increases, and some tender aquatic plants and fine feeds such as barley can be appropriately thrown in. From July to October, it is the peak season for shrimps and crabs. Therefore, the proportion of animal feed should be increased in the diet to increase the protein content of feed. When the young shrimp hatched, their diet changed with the growth of the young shrimp. In July, organic fertilizer should be less applied, and more artificial feeds such as rice bran, bean cake, bran, snail, fish meal, etc. should be added. The animal feed is generally about 20%, and the total weight of shrimp, crab and crab is 3% to 5%. 2. Feeding time and position feeding can be divided into morning and evening respectively. The amount of feeding in the morning accounts for 1/3 of the day and 2/3 in the evening. It can be thrown along the pool at the shore, so that the bait can be distributed evenly, the individual's feeding conflict can be reduced, and the chances of crab fighting and fighting can be reduced. In order to facilitate the observation of the feeding situation, several observation tables can be set at the bottom of the pool at different locations in the pool. The observation table can be made of a 30 mesh fabric measuring 1 meter by 1 meter. Check food, shrimp and crabs, etc. to determine the number of feedings to avoid shortages and waste. 3, Water Quality Management The most important thing for shrimp and crab polyculture is to manage the pool water to ensure that the water quality is “fresh and refreshingâ€. Excessive water quality directly affects the crusts of shrimps and crabs. Shrimp and crabs are susceptible to disease. Therefore, in addition to regular exchange of pool water, quicklime must be applied regularly to adjust the water quality to meet the growth requirements. From March onwards, fresh water is added every 3 to 4 days or every other day, each time adding 0.1 to 0.2 meters of water. When the transparency is less than 30 centimeters, the water must be changed, and the water should be changed by 1/3 each time. In July and August, due to rising temperatures and rapid changes in water quality, the first step is to increase the amount of water exchanged and shorten the interval. The second is to control the color of water. Regularly spill quicklime and splash it with 10mg/kg Quanchip every 15 days or so. The third is to constantly pay attention to the status of dissolved oxygen in water and avoid hypoxia in shrimp and crabs. 4. The patrol pond should adhere to the patrol pond every day to observe the activities of the water color, shrimp, crab and fish, find out the problems, and immediately handle it to avoid unnecessary losses. Especially in the summer and autumn season, it is necessary to pay attention to whether the shrimps and crabs are subject to anoxic floating heads. If it is found that the hypoxia of the shrimps should exchange the pool water in time, and administer oxygen-enhanced medicines. If there are oxygen-increasing machines, they should be opened in time for oxygenation. In addition, anti-theft and anti-escape operations must be done. (4) From the time of the arrest, it may be determined according to the market conditions whether the shrimps and crabs will be arrested and sold in time. The habit of crabs is to start climbing in October in autumn, so they can use their characteristics to capture on the shore during the night, collect them and then raise them to small crab gates or cages for sale. This method can catch about 60% of crabs, and the rest can be caught in cages or dry ponds. When the crab is caught, the size of the crab can generally reach 100-150 g/piece, and the large one can reach 200-300 grams/piece. Green shrimp can be caught with shrimp nets, and the rest can be reduced to 0.5 to 0.8 meters with nets repeatedly caught and the remaining dry ponds captured. The normally grown young shrimp can grow to 4 to 6 centimeters by the end of the year. The stock that is stocked with crab species is about 0.5 kg of squid. By the end of the year, it can grow into commercial fish of 1.5 to 2 kg.
Normal Model Xray Radiation Lead Glasses,Surgical Doctor X-Ray Lead Eyewear,CT Scanning Lead Glasses,X Ray Lead Goggles
Longkou Kangxie Medical Instrument Co., Ltd , https://www.lkkangxiemedical.com