Redfin Oriental Pure Pond Culture Technology in Jinhu County, Jiangsu Province
Relying on the project of "Integration and Demonstration of Puffer Fish Ecological Breeding Technology", Jinhu County, Jiangsu Province, conducted trial culture of redfin oriental pufferfish in a pond of 9.8 mu for two consecutive years in 2018 and 2019, and achieved a good average profit of 5690 yuan / mu, and the economic benefits far exceeded those of other conventional fish farming, becoming a new way and new highlight to promote the economic growth of local fisheries. The preliminary exploration techniques of the redfin oriental pufferfish are summarized and introduced as follows for the reference of farmers.
First, pond conditions
1. Pond site selection Should choose to build or rebuild ponds in places close to water sources, sufficient water quantity, fresh water quality, stable water temperature, no pollution sources, power facilities, and convenient transportation.
2. Pond conditions The pond is rectangular, the area is 5 to 10 acres, the water depth is 1.5 to 2.0 meters, the width of the pond is 2 to 3 meters, the pool slope ratio is 1: (2.5 to 3.0), the pond slope is protected by 30 purposes of polyethylene mesh sheet, the soil is loam, and the bottom of the pond is basically flat. Culture ponds should have separate inlet and drainage systems to control water levels, regulate water quality and reduce disease. Aquaculture ponds should also be equipped with corresponding mechanical and electrical equipment, taking the 5 acres of pond mouth as an example, should be equipped with 2 1.5 kW aerators, 2 3 kW pumps, 1 120 watt feeder.
Second, prepare before stocking
1. Pond mouth trimming In winter, drain the pond water, remove weeds and debris, dig up too much silt, retain about 10 cm of silt, strengthen the pond mound, plug the loopholes, freeze and dry the bottom of the pond throughout the winter, in order to accelerate the weathering decomposition of organic matter in the sediment.
2. Clear pond disinfection Start clear pond disinfection 15 to 20 days before the seedlings are released, first use 100 kg /mu of quicklime dry method to clear the pond; 7 to 10 days of water injection of 80 ~ 100 cm, and then use 10% bromellohmide disinfection, the dosage of 250 ~ 300 g / (mu · rice), in order to quickly and completely kill pathogenic bacteria, parasites (eggs) and wild fish and other harmful organisms.
3. Fertilization and bait 5 to 7 days before the stocking of fish species, a long-acting bio-organic fertilizer water king is thrown into the pond, with a dosage of 1 kg/(mu · m), in order to cultivate plankton and provide biological bait for the seedlings that will be put into the pond. After that, every 10 to 15 days, apply an amino acid fertilizer water treasure once, with a dosage of 500 ml / (mu · meter), to improve the rate of plankton reproduction, increase the density, and provide a steady stream of biological bait for the redfin oriental pufferfish.
4. Set up a feeding platform The feeding platform is set up in the middle of the north bank of the pond, using wooden or cement boards as a countertop and extending to the water surface of the pond for about 5 meters. A wooden stick or cement pole is used as a pile under the table, and the feeding table is fixed to a height of 40 to 50 cm above the highest water level of the pond, and a feeder is installed on the countertop that extends to the end of the pond.
5. Fence the feeding field In front of the feeder, a square floating food field is surrounded by a 20 mesh polyethylene mesh cloth, with an area of 20 to 30 meters2. The lower edge of the mesh cloth is 30 to 40 cm into the water, the outer side of the mesh cloth is fixed with bamboo poles and wooden sticks, and the upper edge of the mesh cloth is made of square foam plastic × 10 cm or a plastic pipe with a diameter of 10 cm as a float to prevent the feed rafting outside the field. Small microporous oxygenation equipment can be installed in the dining field to increase the dissolved oxygen of the water body in the dining area, enhance the appetite and absorption and digestion of the redfin oriental pufferfish, and promote its health and rapid growth.
3. Stocking of seedlings
1. Seed quality The redfin oriental pufferfish seed must meet the quality requirements of fattening, symmetrical body, bright body color, neat specifications, strong water topping ability, strong feeding ability, no deformity, no injury, no pests. The redfin oriental pufferfish seed trial cultured in Jinhu was selected and purchased from the puffer fish fry breeding base of Jiangsu Zhongyang Group.
2. Seed transportation Seedling transportation should follow the "three fast" principles of fast loading, fast transportation and fast release. The entire transportation process from the seed to the mouth of the breeding pond must be tightened and implemented layer by layer. It is typically shipped in plastic oxygen bags 45 cm × 75 cm. The choice of plastic oxygen bagging has the advantages of small size, light weight, easy to carry, large shipping density and high survival rate. It is preferable for seedlings to be transported in the morning or evening, but the temperature in the morning and evening is low, the activity of the seedlings is small, and it is not easy to be injured during transport. The general transportation time is 6 to 8 hours, and the time is too long to produce hypoxia, fatigue, injury and other phenomena, affecting the survival rate.
3. Seed stocking The stocking size of redfin oriental pufferfish seedlings is 3 to 5 cm, the density is 2000 to 2500 fish/mu, and the time is from the end of May to the beginning of June. On the basis of the successful intensive culture trial of redfin oriental pufferfish in 2018, some small-sized silver carp, bighead carp and crucian carp species were combined in 2019 to improve pond productivity and comprehensive economic benefits. Stocking of seedlings is detailed in Table 1.
Table 1 Details of the stocking of redfin oriental pufferfish in 2019
4. Seed disinfection The redfin oriental pufferfish seed needs to be disinfected with 5% salt water solution for 10 to 15 minutes before being stocked into the pond, and the silver carp, bighead carp and crucian carp seed need to be disinfected with 15 to 20 mg/l potassium permanganate aqueous solution for about 10 minutes to kill the seed surface bacteria, water mold and parasites (eggs).
Fourth, aquaculture management
1. Reasonable feeding Since the nutritional needs for the growth of redfin oriental pufferfish have not yet been fully explored, standardized special compound feed has not yet been widely promoted. Most farmers currently substitute perch or eel compound feed. We feed sea bass compounds with a protein content of 40%.
3 days before the redfin oriental puffer fry are planted in the pond, the pre-bred plankton in the pond is used as bait, and no other bait is fed. From day 4 onwards, compound feed (crushing material) is fed in the food field for domestication, and the redfin oriental pufferfish are lured to the food field to eat in groups, and a good habit of "fixed-point, timed and quantitative" feeding is developed. After 7 to 10 days of successful domestication, the automatic feeder is used to feed, and the "three meals a day" system is implemented, that is, once a day is fed once a day from 7:00 to 8:00, 13:00 to 14:00 and 18:00 to 19:00. The main peak of the daily feeding of the redfin oriental puffer is 18:00-19:00, and the secondary peak is 7:00-8:00, so it should focus on morning and evening feeding, and evening feeding is particularly important. The particle size of pellet feed fed in the early stage of breeding is 1 to 2 mm, and the daily feeding rate is 6%-8%; the medium-term feeding particle size is 3-4 mm, and the daily feeding rate is 4%-5%; the late feeding particle size is 5-8 mm, and the daily feeding rate is 3%-4%. The specific feeding amount should be flexibly controlled according to the weather, water temperature and fish feeding and growth, generally 20 to 30 minutes after feeding basically eat or eat to 80% full. Silver carp and bighead carp use the plankton in the pond as bait, and crucian carp feed on the residual bait in the pond, and there is no need to feed other bait.
2. Scientific water transfer Add water once a week, about 20 cm each time; change the water once a month, replace 30% of the bottom old water each time, keep the water fresh, and the stable transparency is 30 to 40 cm. Turn on the aerator to oxygenate in a timely manner, keep the dissolved oxygen of the pool water at more than 5 mg/l, and let the redfin oriental puffer grow under the superior conditions of enjoying "oxygen regulation". Sprinkle micro-ecological living water once every half a month, with a dosage of 200 to 300 grams / (mu · rice), in order to effectively remove toxic and harmful substances in the water, adjust the pH at 7.5 ~ 8.5, and maintain the "fat, live, tender, cool and stable" of water quality. The bottom of the fish pond is sprinkled once a month, and the dosage is 500 to 1000 g/(mu · m) to restore the bottom environment and maintain the ecological balance of the bottom.
3. Disease prevention and control Effectively do a good job in the prevention and control of the following diseases:
The first is to disinfect the dining area once a week, dissolve 1 kg of 30% chlorine bleach powder in 50 kg of water, and sprinkle it on the dining area before feeding to prevent a large number of pathogens from growing. The second is to sprinkle 20% of the bacterial poison double killing once every half a month, with a dosage of 100 ml / (mu · meter) to kill bacteria, fungi and viruses in the water body. The third is to sprinkle the net fish and insects once a month, and the dosage is 400 to 450 grams / (mu · rice) to prevent the occurrence of parasitic diseases. Once the pond fish become ill, the cause should be diagnosed in time, the right medicine (the use of illegal drugs is strictly prohibited), early treatment and rapid treatment, and the disease should be eliminated in the "bud". Since the redfin oriental pufferfish is sensitive to the drug dose and treatment time, the drug should be correctly calculated according to the requirements of the drug instructions, the amount of pond water and the amount of pond fish should be correctly calculated, and the amount of application and treatment course should be reasonably determined to ensure the safety of medication.
4. Daily management Adhere to each pond patrol once a day in the morning and evening, observe the activities, feeding and growth of pond fish, so that you have a good idea and a good response; check the use of breeding facilities and the operation of mechanical and electrical equipment, and find damage and replace it in time. Regularly test the water quality of transparency, pH, dissolved oxygen, temperature and ammonia nitrogen, and take timely improvement measures. Usually, carefully fill in the records of the mouth of the breeding pond to provide a reference basis for feeding, water transfer and disease prevention.
After 4 to 5 months of careful breeding, the average size of the redfin oriental pufferfish seed released that year was 125 g/tail, the return rate was 90.6%, the yield was 260.5 kg/mu, and the benefit was 5800 yuan/mu, which was twice the local conventional fish farming benefit.
