Methods and techniques of three-dimensional Culture of Tilapia

The cost of three-dimensional aquaculture is relatively low, and when the fish price is low, the profit space is large and the maneuverability is strong. How to further improve the efficiency of three-dimensional culture from the management skills has become the main problem at present.

In recent years, due to the rising rents of fish ponds, rising feed prices, and limited water resources in many areas, tilapia diseases occur from time to time, while the prices of finished fish are sometimes high and sometimes low, and the market is not optimistic. How to reduce breeding costs and risks has become a common concern of farmers.

1. Benefit analysis of tilapia culture model.

Taking the model of monoculture tilapia as an example, if the whole feeding process is adopted, the cost of tilapia culture is about 3.5-4 yuan / jin, which can be raised twice a year. The mode of mixed culture of fish and shrimp is adopted, and the whole process is fed. In this mode, the culture cost of tilapia is about 3-3.5 yuan / jin, and one fish can be raised in one year. And adopt the three-dimensional culture mode, tilapia and four big domestic fish mixed culture in the pond, adopt semi-feeding method, the cost is about 2-3 yuan / jin, can also raise one fish a year.

Market price determines the way out of fish, single culture cost is too high, mixed culture often can only break even, three-dimensional culture cost is relatively low, when the fish price is low, the profit space is larger, the maneuverability is strong.

Second, the problems existing in the three-dimensional culture model.

At present, there are still the following problems in the three-dimensional culture mode of tilapia: first, due to semi-feeding culture, the growth rate of fish is slow, and the growth speed is uneven, so that the specifications of commercial fish are irregular, so it is easy to concentrate on the peak of fish production at the end of the year, and the fish price is often not good at this time. Second, when there is too much manure of livestock such as pigs and ducks, it is easy to make the biological chain of the water body out of balance, and the water quality is easy to deteriorate, which has a great influence on the growth rate of fish in the water body; third, when the water quality in the pond is a vicious circle, fish are prone to disease or even death; fourth, there may be drug residues in breeding environment, seedling, feed, aquatic animal medicine, livestock medicine and other links. Fifth, the farmers' awareness of scientific management is weak, and they do not pay enough attention to the prevention and control of fish diseases and water quality regulation, which can easily cause economic losses due to the deterioration of water quality.

Third, the management skills of three-dimensional culture model.

1. Reasonable close planting and proper collocation

Taking about 20 mu fish pond as an example, assuming that the water depth of the fish pond is 2.5-3m, the proportion of seed and fry can be as follows: 40-50 fish / mu, 30-40 fish / mu, 300-400 crucian carp / mu, 1300-1600 tilapia / mu, and then match other fish species properly. Big-headed fish and mackerel can be reared twice a year, while other fish can produce one a year. In fact, no matter which kind of culture mode, we must properly arrange the culture density according to the actual culture environment and master the production cycle.

2. Graded culture

It is suggested that farmers spend more time to concentrate the purchased seedlings in small ponds to large size seedlings and then separate them through the ponds. This operation is not only conducive to management, concentrate feeding, but also improve the survival rate of fry, at the same time, it can be more accurate to master the culture density after passing through the pond. In the process of farming, taking turns fishing and stocking can not only improve the utilization rate of fish ponds, but also increase the economic income of ponds, and more importantly, it is conducive to the management and control of the main production ponds.

3. Pay attention to insecticidal, sterilization and water disinfection

The three-dimensional culture of tilapia should focus on prevention and the combination of prevention and control to reduce the incidence of fish disease. Too many insects and bacteria will lead to a great decrease in the feeding capacity of fish, slow down the growth rate, reduce the conversion rate of feed, increase the cost, and even cause a vicious circle, an outbreak of fish disease, and serious fish death. During the culture management, the fish should be tested regularly every month to see if there is any insect infection, especially the tilapia before 100g should pay attention to killing insects frequently, and after 100g should be killed regularly once a month. The basic principle of killing insects first and then sterilizing should be followed in operation.

4. pay attention to the regulation of water quality

"Fish culture first water", only when the water environment is good, can we achieve the effect of saving materials, less disease, and faster fish. Farmers should often detect the pH value, ammonia nitrogen and nitrite content of aquaculture water, and adjust the water quality according to the actual situation. In the process of culture, the aerator should also be used reasonably and part of the culture water should be replaced at the right time. In rainy or muggy weather, the aerator is usually turned on at noon for 2-3 hours to neutralize the water temperature, increase the amount of dissolved oxygen in the water and volatilize ammonia nitrogen. The water body of fish pond was replaced by slow discharge and slow irrigation.

Water transfer is particularly important in the three-dimensional culture mode of tilapia, especially when the air temperature and water temperature is too high from June to September, it is easy to induce tilapia streptococcosis. At this time, farmers should be vigilant and do a good job of prevention in advance.

5. Effective use of livestock manure and rational feeding of full-price feed

The main results are as follows: (1) the emphasis of feeding feed in the three-dimensional culture model of tilapia is "heavy at both ends and light in the middle". Before 50-100 grams of tilapia, full-price feed was given priority to, supplemented by livestock manure, to promote the early growth and development of tilapia. When tilapia grows to 100-250 grams, it is mainly livestock manure, combined with full-price feed to achieve the purpose of saving breeding costs; when tilapia reaches 250-300 grams, reasonable feeding of full-price feed can improve the growth rate of tilapia and increase the meat yield of tilapia.

(2) in the process of breeding, the amount of feed should be increased or reduced according to the weather, the change of water quality and the intake of fish.

(3) every month, antibiotics, liver protection and other drugs are regularly mixed into the feed to enhance the immunity of tilapia, which is especially important from June to September every year, usually once or twice a month. (avoid using antibiotics and banned drugs in aquaculture)