Fund project: Pond culture technology of ussuri mullet
Fund project: Hunan Provincial Aquatic Industry Technology System Subsidy Fund
_Qin Yuxiang
In 2019, the Yueyang Experimental Station of Hunan Aquatic Industry Technology System introduced Ussuri mothus and trial reared it at the demonstration base of Zhongzhou Fishery Seed Farm in Yueyang County, and the breeding was successful, reaching an average size of 305 g/tail and an output of 788 kg/mu. In 2020, the pond culture experiment of Ussuri moundus was carried out in the demonstration and display base - Xiangyin County Fishery Science Research Institute, and the net profit per mu was 8 303 yuan / mu, and the economic benefits were considerable, and the technology is summarized as follows.
1. Materials and methods
1. Pond conditions
Ponds require sufficient water sources, pollution-free, convenient transportation, and convenient drainage and irrigation. The pond is rectangular, the bottom of the pond is flat, the area is generally 5 to 15 acres, the pool depth is 1.8 to 2.5 meters, the water depth is 1.5 to 2 meters, and each mu is equipped with an aerator according to 1 kilowatt.
2. Prepare before stocking
20 to 30 days before the stocking of fish species, the water depth is generally 20 cm, and the quicklime is 100 kg/mu for disinfection to eliminate wild trash fish and pathogenic bacteria. Ponds are exposed to 7 to 15 days with 60 cm of water and fertilized, bio-fishing fertilizer of 5 kg/mu and a small amount of fermented manure is applied, and gradually added to 1.5 m after 7 days of fertilization. 1 to 3 days before the stocking of fish species to do a good job of pond water toxicity testing, toxicity testing with white porcelain pots fill the pool water, put 7 to 10 tails of 10 to 20 cm long four large fish test water for 1 hour, no abnormality can be.
3. Fingerling stocking
The suitable water temperature for the growth of ussuri monsoons is 15 to 30 °C, so the stocking time of fish species should be from mid-March to early May, and the water temperature is stable at 15 °C. Fish species are stocked with a size of 6 to 10 g/tail and a density of 8,000 to 10,000 fish/mu, along with 100 silver carp with a size of 100 to 200 g/tail and 50 bighead carp with a size of 150 to 250 g/tail. Before entering the pond, the fingerlings are soaked in 4% salt water for 15 minutes to kill the parasites and pathogens.
4. Daily management
(1) Feed feeding. Feeding adheres to the principle of "timing, fixed point, qualitative and quantitative", and generally chooses floating puffed feed, with feed protein levels of 38% to 40% and crude fat levels of more than 7%. The amount of feeding throughout the day should be determined according to the total weight of the fish in the pond, water temperature and feeding, and it is advisable to feed in 20 to 30 minutes for each feeding. Feeding twice a day, 30% of the total feeding volume of the whole day at 6-7 o'clock and 70% of the total feeding amount of the whole day at 18-19 o'clock. The bait rate is about 2% at 13 to 25 °C, the bait rate is about 3% at 25 to 35 °C, and the feeding rate is not fed when the water temperature is lower than 13 °C or above 35 °C. As the fish grows, adjust the particle size of the feed in a timely manner.
(2) Water quality control. The pond water depth is maintained at 1.5 to 2.0 meters, and 4 to 5 water celery dishes with a diameter of 1 meter are planted per acre. Absorb ammonia nitrogen and other nutrients; change the water once every 20 to 30 days, and the water exchange amount is 1/5 to 1/3 of the whole pool; every 10 to 15 days, sprinkle the whole pool with quicklime 10 kg/mu of water to adjust the ph of the water body; regularly adjust the water quality with photosynthetic bacteria and Bacillus to ensure that the pool water is "fat, alive, tender and refreshing".
(3) Reasonable oxygenation. The rational use of aerators is also one of the keys to the success or failure of aquaculture. The aeration function can increase the oxygen content in the water, purify the water body of the fish pond, and improve the pond environment. The use of the aerator follows the principle of "three open three not one more", "three open" refers to the noon on a sunny day, in the morning during thunderstorm weather, and in the middle of the night when the rainy weather is continuously rainy, "three noes" refers to the feeding feed, evening, rainy day noon should not open the aerator, "one more" refers to the lack of oxygen to open more aerators. The dissolved oxygen of the whole process of ussuri mullet culture in the pond water shall not be less than 4 mg/l.
(4) Disease prevention and control. Adhere to the principle of "prevention first, prevention is more important than treatment". Morning, middle and evening patrols of the pond to observe the activity, feeding and growth of fish. Regulate water quality through water celery and probiotics, use quicklime to adjust water ph, and select low-toxicity, low-residue and efficient drugs to prevent and control diseases in strict accordance with the requirements of pollution-free aquatic products.
Second, the results of breeding
5 acres of test pond, 50,000 ussuri anchovy species with a size of 6 to 10 g/tail were stocked on March 27, and at the end of November of the same year, they were fished and listed, and the total production of ussuri mutton was 4 100 kg, with an output value of 98 400 yuan; the average size was 315 g/tail, the yield was 820 kg/mu; and the total output of silver carp was 1 033 kg, with an output value of 9 297 yuan. The total output value was 107 697 yuan, the total investment was 66 180 yuan, the total profit was 41 517 yuan, and the profit per mu was 8 303 yuan,