Feeding management
Feeding management
In the process of aquaculture, artificial feeding bait types are compound feed, chilled fish, snails, clams, soybean meal, wheat and corn. Bait feeding should adhere to the principle of "meat and vegetables, two fine, middle coarse".
In the early stage of aquaculture (March to May), feed mainly with feed, supplemented by part of the fresh fish, snails and clams, etc.; mid-farming (June to August), feed watercress, soybean meal, wheat, maize and other plant bait is the main, animal bait feeding should be reduced to prevent precocious maturation of the crab and the occurrence of gastrointestinal disorders; the late stage of aquaculture (September to November), feed with feed, fresh fish, snails and clams, and other animal bait. and clams and other animal bait, moderate feeding part of the water grass, soybean meal, wheat, corn, etc., in order to meet the nutritional needs of the late growth and fattening of river crabs.
Feeding is done once a day in the morning and once in the afternoon, mainly in the afternoon, accounting for 70% of the daily bait. The activity range of the river crab is small, the bait feeding requirement is strip-like, uniformly cast in the shallow water, the baiting point area should account for more than 30% of the area of the crab pool. The feeding quantity should be controlled flexibly according to the feeding intensity, season and temperature change of river crabs, and it is generally preferable to finish the food within 2 hours after baiting.
Two, daily inspection
The main points of river crab culture technology and daily management
The main thing is to insist on inspecting the ponds once a day in the morning and in the evening, and the main tasks are:
One of them is to check the integrity of the anti-escape facilities, and to find out that the damages should be repaired in time.
The second is to check the activities of the river crab and eating situation, found that there is residual bait should reduce the amount of bait.
Third, check the water quality changes and the moult and growth of river crabs, found abnormalities should be taken in a timely manner to respond to the measures.
The fourth is to fill in the pond records, detailed records of stocking, feeding, water quality, disease, production and sales, and organize the archives to save, for the next year's aquaculture production to provide a reference basis.
Three, water quality management
Water quality management
Throughout the breeding process, the overall requirements for water quality is "clear, new, tender, cool. Generally maintain the ph value of 7.5 ~ 8.5, transparency of 30 ~ 40 cm, dissolved oxygen for more than 5 mg / liter, water temperature of 25 ~ 28 ℃.
Monthly use of em bacteria, Bacillus subtilis, the bottom of the net treasure and other biological agents 1 time, decomposition of organic matter in the pool, reduce ammonia nitrogen, hydrogen sulfide and other toxic and harmful substances, can play a role in improving water quality and prevention of disease. Often use microporous oxygenation equipment to increase oxygen, in order to maintain the dissolved oxygen in the pool water at more than 5 mg ∕ liter, to create an excellent environment for the growth of river crabs.
Four, water and grass management
Water and grass management is an important technical link. When the coverage of pond water plants is less than 40%, it should be supplemented with drought-loving lotus grass (water peanut) and duckweed in time. Drought-loving lotus grass purifies the water with obvious effect. Floating duckweed is the plant bait that river crabs like to eat, but floating duckweed has a strong reproduction ability, when the coverage area is more than 15%, it must be fished out artificially, so as to avoid affecting the photosynthesis of the water body and reducing the amount of oxygen production.
For the sludge and other foreign matter attached to the water plants, you can take the sprinkling of grass protection and other methods of treatment, in order to improve its ability to absorb the decomposition of harmful substances, enhance the effect of water purification.
Five, disease prevention and control
Should follow the "ecological prevention as the main, drug treatment as a supplement" "no disease first prevention, early treatment of disease" principle, through the implementation of strict disinfection of ponds, stocking high-quality seedlings, to create a good environment, Scientific bait feeding and regular feeding of bait and other healthy breeding means, actively prevent and control diseases; through biological agents to improve water quality, reduce the content of harmful bacteria, and then lime, chlorine dioxide and povidone iodine disinfection of the water to control the occurrence of bacterial diseases.
Once the disease is found during the breeding process, it should be diagnosed in time and correctly medicated to control the spread of the disease. Fishing drugs should be highly efficient, low toxicity, small side effects, and not use fishing drugs that are explicitly prohibited by the state.