Essentials of intensive culture of bamboo shoot shell fish in Thailand

If you want to raise Thai bamboo shoot shell fish well, you must have a set of mature culture techniques, which should be integrated into daily management and run through the whole culture process, so as to achieve high yield and ideal economic benefits. □ / Zhong Musheng Thai bamboo shoot shell fish belong to Perciformes, suborder Pongiformes, Pontiformes and Cunninghamia lanceolata in taxonomy, also known as Ophiocephalus. It is a large individual species in the suborder Carpinus. Because of its delicious meat, high nutritional value and great market potential, it is an excellent breed of freshwater fish at present. There are three culture methods of bamboo shoot shell fish in Thailand: co-culture, mixed culture and monoculture. Intensive culture of bamboo shoot shell fish in Thailand is a high-yield culture method using water-rich ponds for high-density culture. The growth cycle of bamboo shoot shell fish is longer than that of other freshwater fish. it usually takes 8-10 months from fry breeding (8-10cm) to commercial fish sale, and its growth rate is affected by the type of feed, stocking density, culture mode and daily management. therefore, to raise Thai bamboo shoot shell fish well, farmers must have a complete set of mature culture techniques. Only by integrating the technology into the daily management and throughout the whole breeding process can we achieve high yield and obtain ideal economic benefits. In order to better promote the development of the excellent quality of Thai bamboo shoot shell fish, combined with the author's culture experience in the past ten years, the intensive culture techniques of Thai bamboo shoot shell fish were summarized for reference. First, pond conditions although Thai bamboo shoot shell fish have a preference for their growth environment, but the requirements are not high, generally the old fish ponds can be cultured with a little rectification. However, if the water surface is too small, the unstable aquaculture water body will affect its growth; the water surface is too large, which increases the difficulty of management and inconvenient operation. In order to achieve intensive culture with high density, high yield and high yield, it is best to choose a pond with sufficient water source, no leakage and strong water retention capacity, with a culture surface of 3-5 mu and a water depth of 1.8-2m. Second, thoroughly clear the pond with a small amount of water (about 20cm), 100kg quicklime per mu of water surface, emulsified and sprinkled evenly throughout the pond while it is hot, and ploughed the bottom of the pond with an iron rake the next day. On the fifth day, add water 30cm, then sprinkle it evenly with 5mg/L trichloroisocyanuric acid throughout the pond; add water 30cm on the eighth day, release seedlings on the 12th day (water test), and inject water every five days after release, each time 20cm, until the highest water level. Third, the stocking density is generally controlled at about 3000-4000 tails / mu according to its own culture conditions and level. Fourth, the purebred fry with obvious cloud spots, pure body color, the best body length of about 10cm, uniform and tidy specifications, no damage, no deformity and no disease should be selected. When releasing seedlings, choose cool and sunny weather in the morning. Fish body medicine bath disinfection must be carried out when releasing fry. Specific measures: prepare a wide-mouth bucket or large basin at the edge of the pond, containing 30 jin of water and 0.7 jin of 0.9 jin of salt until it is fully dissolved, cover 200 fish fry with another basket at the same time, soak them in salt water, and when they can't stand jumping, take out the vegetable basket containing fish fry and slowly put them into the fish pond. Repeat this until it is finished. Fifth, the bait Thai bamboo shoot shell fish is carnivorous fish, at present, there are four kinds of food sources: (1) pure chilled fish (small pieces cut by meat cutter); (2) chilled fish (minced meat with minced meat) plus eel; (3) pure dace spray and seedlings; (4) chilled fish mixed with eel, dace spray and seedlings. According to many years of breeding experience, the fourth stage feeding method has a better effect. Therefore, the fourth feeding method is introduced emphatically. After releasing the seedlings, the feeding began on the third day, and the bait was a mixture of chilled fish and eel at 9:1 (it would be better if the bait did not spread to the surimi in the water). For 3-10 days, feed at about 5 p.m., with 1% of the body weight of the fish. Feeding method: raindrops are scattered 3 meters around the edge of the pond. Ten days later, the fish was rained 3 meters around the edge of the pond twice a day at 7: 00 in the morning and 5: 00 in the afternoon. The second month began to put an appropriate amount of low-value live dace spray to form a feeding method dominated by chilled fish mixture and supplemented by active animal feed. After 4 months, the amount of live dace spray was gradually increased, and at the same time, the chilled fish mixture was scattered along the edge of the pond to be fed at a fixed point, thus forming a feeding method in which the chilled mixture was equal to the active animal feed. Feeding method of mixed food: set up a food table at the edge of the pond every 8m or so. The food table can be made of 60 mesh mesh and iron wire with a diameter of 60cm and high 10cm, which can be used to hold bait. Feed 2% of the fish at 7: 00 am and 5: 00 pm every day. At the same time, pay attention to observe the feeding status of bamboo shoot shell fish on active bait (dace spray). When the active bait (dace spray) is insufficient, it should be put in time. After 6 months of culture, the chilled fish mixture was reduced to 1% of the fish's body weight, once a day, fed at 5-6 p.m. At the same time, a sufficient amount of active dace fry was put in to form a culture process which was dominated by active animal feed and supplemented by chilled fish mixture. During this period, the feeding of bamboo shoot shell fish on active animal feed (dace fry) was observed, and the deficiency was found and replenished in time, so as to ensure that there was enough active mud carp spray bait for its feeding until the whole culture period. Sixth, separate cultivation of Thai bamboo shoot shell fish because of its nature is a little lazy and inactive, slow feeding, so that its individual growth rate is very different, in addition, it has the habit of killing each other, so it should be divided into ponds at least during the whole culture period (separate culture). When separated, in order to avoid sunburn, it is best to choose when the weather is cool from September to October. According to its physiological particularity, its scale barbs are very strong, slightly inadvertently, it is easy to cause scales to fall off, so, in separate cultivation, should be careful operation, so as not to cause injury. After the completion of the separate culture process, the mixture of 0.5 mg/L of copper sulfate and 0.5 mg/L of dichloroisocyanuric acid (bromochlorohydantoin) should be sprinkled evenly in the whole pond. 7. Water quality treatment takes technical water change twice a month, that is, irrigation while drainage (convection time 4-5 hours) to maintain the original water level. Lime powder is scattered within 4 m along the edge of the pond every 3 months to ensure that the transparency of the water body is above 30cm. This can also kill and remove moss and local sterilization on the edge of the pond, killing three birds with one stone. Heat preservation and antifreeze Thai bamboo shoot shell fish is a subtropical fish with poor resistance to low temperature. The food intake decreased significantly when the water temperature was 22 ℃, stopped feeding at 19 ℃, frostbitten at 14-15 ℃, frostbitten at 12-13 ℃, severe frostbite at 10-11 ℃, and lethal water temperature at 9 ℃. In the actual culture, we should take the water temperature of 18 ℃ as the critical point. This tipping point, not to mention the north, should be taken seriously by both Guangzhou and Guangdong, so in mid-late November, the winter shed should be built before the water temperature of 21 ℃ comes, so as not to cause unnecessary losses. Ninth, daily management because the transparency of the water body is high, and the bamboo shoot shell fish like shade and fear the light, and the water grass at the edge of the pond without laying pipes at the bottom of the pond can not be removed if it does not affect the feeding, which is conducive to the habitat of bamboo shoot shell fish and preying on active animal bait. Insist on patrolling the pond sooner or later, and timely kill and drive away waterbirds when you find snakes, rats and large frogs. The food used for feeding should be taken out to clean up the sun every day, and problems should be solved in a timely manner. Tenth, disease control leads to the disease of farmed fish is mostly caused by the mass reproduction of pathogenic bacteria (pathogens), their flora and density reach a considerable degree, and so are insect pests. The number of pathogens is so small that even if it invades the fish, it will not cause immune disorder and disease. The traditional concept of disease prevention and treatment is three-part prevention and seven-part treatment, while aquaculture should be seven-part prevention and seven-part treatment. Thai bamboo shoot shell fish have a strong immune function to the disease. the most direct and basic reason leading to the disease of bamboo shoot shell fish is that our daily management and technical level are not yet in place, unable to restrain the proliferation of bacteria (pathogens) in the whole culture process and eliminate it in the bud. Here, several common diseases and insect pests of bamboo shoot shell fish in Thailand and their control methods are introduced. (1) rotifer prevention: when releasing seedlings, 3% salt water is used for drug bath. Treatment: the mixture of 0.7mg/L copper sulfate and ferrous sulfate (5:2) was sprinkled evenly throughout the pond when there was no wind or breeze in the morning. (2) Prevention of oblique tube disease: when releasing seedlings, use 3% salt water for medicine bath, or use potassium permanganate solution for medicine bath. Treatment: the mixture of 0.3-0.4mg/L copper sulfate and potassium permanganate (5:2) was sprinkled evenly throughout the pond when there was no wind or breeze in the morning. (3) Prevention of fixed ciliosis: comprehensive prevention should be carried out to keep the water quality of aquaculture water fresh. The use of drugs and methods is the same as oblique trichomoniasis. Treatment: on the first day, the method was the same as that of rotifers; at noon on the second day, the fresh water was used for convection for 5 hours to maintain the original water level. On the third day, the mixture of 0.3-0.4mg/L copper sulfate and potassium permanganate (5:2) was sprinkled evenly throughout the pond when there was no wind or breeze in the morning. (4) Prevention of ring worm, pseudo-finger ring worm and third-generation insect disease: comprehensive prevention should be carried out to keep the water quality of aquaculture water fresh. You can use 18mg/L 's potassium permanganate solution or 10mg/L 's trichlorfon solution for 15 minutes. Treatment: the mixture of trichlorfon and sodium bicarbonate (1 0.3mg/L 0.6) was sprinkled evenly throughout the pond in the morning. (5) Prevention of printing disease and red skin disease: comprehensive prevention should be carried out to keep the water quality of aquaculture water fresh. The measures are the same as the above water quality treatment. The mixture of copper sulfate of 0.5mg/L and dichloroisocyanuric acid of 0.5mg/L (bromochlorohydantoin) was sprinkled evenly in the whole pond once a month. Treatment: first of all, use a microscope to see if there are insects, if there are insects, the corresponding drugs should be used to kill insects. After 24 hours, the fresh water was used for convection for 5 hours, and the mixture of copper sulfate of 0.5mg/L and trichloroisocyanuric acid of 0.5mg/L was sprinkled evenly over the whole pond the next day, and the bait of oxytetracycline was used to feed it for 5 days. (6) Prevention of parotitis and mumps: comprehensive prevention should be carried out to keep the water quality of aquaculture water fresh. Measures are the same as water quality treatment. The mixture of copper sulfate of 0.5mg/L and dichloroisocyanuric acid of 0.5mg/L (bromochlorohydantoin) was sprinkled evenly in the whole pond once a month. Treatment: first of all, use a microscope to check whether there are insects, if there are insects, the corresponding drugs should be used to kill insects. After 24 hours, convection with fresh water for 5 hours. The next day, the water was sprinkled evenly throughout the pond. On the third day, the water was sprinkled evenly over the whole pond with benzalkonium bromide. At the same time, norfloxacin mixed with bait was fed for 4-5 days. (7) the occurrence of blue and green algae is inevitable in all aquaculture ponds. The large number of blue and green algae do great harm to the culture of bamboo shoot shell fish in Thailand. Therefore, the aquaculture water body should be kept fresh in the daily management. if a large number of green algae are found on the surface of the whole pond (peak period), sprinkle the mixture of copper sulfate of 0.5mg/L and dichloroisocyanuric acid of 0.5mg/L (bromochlorohydantoin) evenly on the whole pond at noon. If it is too serious (gathered in a pile), choose to sprinkle it with 0.5ppm 's copper sulfate and high concentration trichloroisocyanuric acid mixture (dissolved separately and then mixed) for two consecutive days when the breeze blows it to a corner of the pond.