II. Requirements for Water Quality of Rainbow Trout Farming
1, the temperature: This is an important condition, the best water temperature in the four seasons at 12-18 °C, the maximum temperature in summer can not exceed 24 °C.
2, dissolved oxygen: dissolved oxygen in water should be 7mg / L or more, the lowest general can not be less than 5 mg / L.
3, the flow of water: requires a larger flow, flow, large-scale farming, production is also high. Generally 1 litre of water per second, with a production capacity of 100-200 kg.
4, requiring water quality clean, no pollution, no sediment.
Third, aquaculture pond conditions
1. Fish pond shape: The fish ponds of different cultured rainbow trout vary in shape, but they are mostly rectangular. The general length-to-width ratio is 8:1 to -10:1, which can be determined according to the terrain. Maintaining a certain gradient (1/50--1/100) from the inlet to the outlet facilitates water exchange and drainage. Between the pool and the pool can be used terrain classification water layout.
2, fish pond area and depth: roughly refer to the following dimensions: Fish pond category area (m2) depth (m) hatching pond, larvae pond 2-6 0.3-0.5 fry pond 16-30 0.3-0.6 fish pond 50-300 0.6- 0.8 Adult fish pond 100-700 0.8-1.0 Brood fish pond 200-1000 0.8-1.2
3, fish pond construction: fish pond structure is a brick-concrete structure, the inner wall with cement wipe smooth. The inlet and outlet are located in the middle of the fish pond so as to maintain the water level. At the same time, the inlet and outlet must be fenced to prevent fish from being caught.
Fourth, seed and delivery
1. Stocking densities of seedlings: Reference density stage of each culture stage Weight (g) Water temperature (°C) Density (tail/m2) Remarks Before egg yolk absorption 13 5000 Dissolved oxygen 6-8mg Open food 1-2 months 0.5 13 1000-500 Open for food February to February 3 15 500-300 Open for food April to June 15 17 300-200 Open for food June to September 80 19 200-100 Open for food September to December 180 15 100-50 Second-instar fish 1000 15 30 -15 Broodstock 1000-2500 15 3-5
2, seed requirements: a strong physique, specifications, no injuries, no disease.
3. Fish and fingerlings should be disinfected when they are released.
Fifth, the requirements of bait
1. The demand for protein in rainbow trout is 40% to 45%, which requires the food to be comprehensive, the crude protein content is about 45%, the adult fish is not less than 40%, and the feed must have a high fat content. Care should be taken to add minerals and vitamins.
2, bait can be locally sourced, the use of small fish, shrimp, animal viscera, pig blood, silkworm cocoons, cockroaches and other animal raw materials and bean cake, wheat flour, corn, bran, vegetables, etc. in different stages of mixing in different proportions processed into particles Feeds are fed. For example, animal foods can account for about 60% of the seedlings, about 50% of the adult fish, and about 40% of the broodstock.
3, the food must be fresh. It is forbidden to use moldy bait.
Sixth, daily management
1. Feeding: Adult fish are fed twice a day. At 9 a.m. and 15 p.m., seedlings can be fed 1-2 times a day. The daily feeding amount is based on the weight of the fish, juveniles account for about 3%-4%, adult fish 1%-2%.
2. Screening fish: Rainbow trout rearing for a period of time, individual size differences will occur, to be regularly screened to keep the size of fish in each fish pond is basically the same.
3, to strengthen the prevention and treatment of fish diseases, found that diseased fish should immediately take treatment measures, dead fish should be promptly removed.
4. When oxygen deficiency occurs, oxygenation measures should be taken to prevent fish from suffocating death.
I. Introduction to Rainbow Trout Rainbow trout are native to the foothills of the Mount Shasta in California on the west coast of the United States and were later introduced to dozens of countries for artificial breeding. Rainbow trout is a cold-water fish with a water temperature of 2-25°C and an optimal water temperature of 12--18°C. Rainbow trout meat is delicate, delicious, less thorny and nutritious, and has been listed as a valuable fish internationally. Rainbow trout farming in China began in 1959. North Korea introduced a small amount of ovipositor eggs and fry, first in Heilongjiang, and later expanded to other provinces such as Beijing, Shanxi, and Liaoning. Now rainbow trout farming has spread over more than 20 countries across the country. Provinces. Our province has relatively abundant cold water resources, such as cold springs in mountainous areas, bottom reservoir water discharged from large and medium-sized reservoirs and power generation. The temperature is stable all year round, and rainbow trout can be developed. Moreover, our province is located in East China, close to the open coastal cities, the market demand is large, and the development potential and economic benefits of rainbow trout breeding are all considerable.