Norway of Seawater Aquaculture Technology
Norway has been recognized as the world the most successful model of Shanghai water aquaculture, first try to raise the Atlantic salmon in the late 1960 s to 70 s success, in just 30 years, the water of the sea area from scratch, and for the development of aquaculture technology in the world the most mature, the most rapid development, benefit is the best country. It USES the large-scale anti-wave culture construction technology, perfect compound feed and feeding technology, vaccine research, automatic removal of dead fish, fish automatic counting and environmental management, etc., are walking in the world. Aquaculture production of 7500 t, 1980, 1990 1990 t, 460000 t, 1999, 2000 2000 t, 500000 t, 2004, the average annual growth rate of 28%. Farmed fish, 95% is the Atlantic salmon, trout, a small amount to 95% of production for export. At present, the Norwegian aquaculture license issuing more than 800, about 30 hatcheries, creating more than 300. Perimeter 60 ~ 120 m of the nation's PE circle area more than 5300, more than 200 breeding, direct employees about 27400 people, an annual output value of more than $3 billion, seawater aquaculture as Norway's second largest pillar of national economy. Advanced facilities, good environment, excellent bait, healthy breeding, gene engineering, disease control, vocational education, scale, etc., determine the Norway now good breeding benefit. Norway in recent 10 years, according to relevant materials, the production cost reduced to 16 from 53 Norwegian kroner/kg Norwegian kroner/kg, the main experience and technology are as follows:
1. The progress of breeding technology and industry development
Norway's aquaculture attaches great importance to the development of new technology, every year the cages fish collecting 5% of the total output value ($150 million) to return for development research, Norway's strong development funds. Scientific research units to cooperate with hundreds of salmon farms in Norway, for continuous high efficiency raise salmon industry laid a solid foundation, the technology progress promoted the development of aquaculture (table 2).
2. The small cages bigger cages, nearshore area into offshore area
In recent 20 years, a big step forward every five elderly volume in Norway, from single 20 years ago to 541 m3 of aquaculture water body at present of 19494 m3 (table 3), the forward net weight of 7 ~ 8 t, and replace the net fishing catches up, using the crane to lift. Amplification of the cages specification, further improve the breeding environment, expand the farmed fish activity space, improve the labor productivity. In terms of the constructional, in addition to the polyethylene (PE) circular structure the cages, and steel pallet cages and tension leg cages (TLC), etc.
The process evolution of Norway aquaculture Atlantic salmon
Norwegian forward 20 years development
3. nutritional feed and feeding technology
Norway in 1970s is mainly manual cage feeding, 80s by dry automatic feed, in 90s 2000 by extrusion feed, high energy feed and feeding control system. In the diet formula, by reducing the content of protein and phosphorus and increasing the content of fat, the nutrition of the bait is more balanced. In the feeding technology, operating entirely by computer, can accurately quantitative timing fixed-point automatic feeding; according to the growth of fish, appetite and water, climate change, bait, bait by sonar, television and video collection system, automatic correction of feeding; automatic recording by the daily feeding time, location and quantity. The sensor can detect not feeding and sinking bait, and sends the signal to the computer to stop feeding. The length of the pipe is up to 600m. Nutritional feed and advanced casting technology, the feed conversion rate increasing from 6:1 in 1970s to the current 1:1. High energy feed and feed control system of new development, food conversion rate can reach 0.7:1.
4. fish vaccine and immune prevention and control technology
Norway has developed oral, vaccinated and immunological enhancers successively in the prevention and control of fish diseases in net cage. The 4 kinds of vaccines can be injected with mixed injection. The method is to soak 20s in the anesthetic liquid and injecting into the abdomen of the fish with a injection. After one injection, it can be immunized for life. The price of the vaccine is 1.5 yuan per yuan (1000ml/). The price of each fish is only 4ml, and the price is very low. In disease management, the establishment of fish disease diagnosis services, early detection of disease symptoms, isolation quarantine and disease of fish; training industry to develop good breeding habits, strengthen the communication between practitioners. The establishment of an effective disease control system has greatly improved the survival rate of the culture, and also reduced the risk and cost of the culture.
5. information system
Now with the help of the Internet technology, the farms, breeding, processing plants, feed factory and market, the financial sector together, accelerate the transmission of information, increase the amount of information, so that the distance of farms outside 10km headquarters can clearly know the feeding of fish.
6. biomass control
Biomass control is actually the density control of fish. If the density is too low to reach the design load of the production plant, the efficiency will not be ideal. If the density is too high, it will cause slow growth, easy to get sick, and environmental pollution. Net cage culture in Norway is a year-round catch. The total weight of fish in the cage is maintained at a certain level all year round (25kg/m3). Therefore, it is very important to strengthen biomass monitoring. The techniques for measuring biomass include infrared monitoring and stereoscopic photography.
7. germplasm selection and seedling cultivation
Through many years of selection breeding and genetic engineering technology, we not only increased yield, but also improved the quality (fish flesh tissue tightness and color), making fast growing, good resistance and strong disease resistant breeding fish take up the main body of aquaculture. At present, the 80% of the Atlantic salmon, which is cultivated in Norway, is supported by a fine line. On the promotion of the 2 age salmon, the continuous frying fishes were transferred to the outdoor breeding area less than 10h in the daytime, so that the 2 year old salmon, which was 18 months old, could be shortened to 8~10 months, and the 2 age salmon could be cultivated in low season, so that all kinds of cultured fingerlings could be provided throughout the year. In adult fish, using artificial light growth method, the weight increased by more than 20%, avoid sexual maturity and reduce the risk and increase the growth rate of disease and death, nor will raise adult weight decreased.