1. Breeding environment requirements

The area of ??the bass breeding pond should not be too large. The pond is too small, the water body is narrow, and the dissolved oxygen is insufficient, making it difficult to produce high yields; the pond is too large and too deep, which is not conducive to production operations. . It is suitable to use 8 to 12 acres and a water depth of about 2 meters. It has a sandy loam substrate with less silt. The bottom of the pool is flat and slightly inclined toward the drainage outlet. The water depth is 1.54 meters. The drainage and irrigation system is complete. The water source is sufficient, fresh, pollution-free, and the water quality is good. . It is best to set up inlet and drainage gates in the pond, leading to the inlet and drainage rivers respectively, and do not reuse the breeding water to avoid secondary pollution. Divide the pond into small pieces with fine mesh to make it easier for the fry to feed. An aerator is equipped for every 1.2 to 1.5 acres of water surface, and a water pump must be equipped to ensure that new water can be replaced at any time. A diesel generator is required to prevent the pond from becoming deprived of oxygen during a power outage.

Ponds used to breed bass must be dried, dredged and exposed before releasing seedlings. Disinfection should be carried out half a month before the seedlings are released. Apply 150 kilograms of quicklime per acre or use 20 mg/L bleaching powder with an appropriate amount of pond water for disinfection. If the seedlings have not been exposed to the sun in a dry pond, break up the tea bran and soak it in water and splash it throughout the pond; if the pond has been dried, For those exposed to the sun, release about 10 cm of water 10 to 15 days before stocking, use 80 to 100 kilograms of quicklime per acre, and add 5 kilograms of bleaching powder the next day. Sprinkle the water into the entire pond to clean and disinfect the pond, and completely remove wild fish.

2. Cultivate stocking fry

The frying time is from early December to March of the following year. The bass fry caught from the sea area are 1.5 to 2 cm long and must be desalinated to salt. Only when the salinity is 4‰~7‰ can it be put into a temporary breeding pond with a salinity of 1‰ for temporary cultivation. The general stocking density is about 8,000 fish per acre. Choose to release the fry at noon on a sunny day. At this time, the water temperature and dissolved oxygen are high, which can reduce the discomfort of the fry. The fry are disinfected with water and put into the prepared grid. Since high-density breeding requires a lot of bait, and bass rarely feed on leftover bait at the bottom of the pond, a small amount of crucian carp, tilapia or bream (omnivorous) should be released per acre after removing the net, and a small amount of silver carp (filter feeder) should be added. To reduce water pollution and increase breeding efficiency.

On the second day after entering the pond, start feeding fresh food such as zooplankton and red worms. Slowly mix the fish paste, floating particles and fresh food with the fresh food, and then gradually acclimate it to feeding stir-fry. Crushed surimi, floating pellet feed. During the temporary raising period, use 0.3 international units of strong chlorine or 15 international units of formalin for disinfection once a week. Three days before the start of feeding, 0.5 grams of furazolidine, 3 grams of oxytetracycline, and 1 gram of vitamin C were taken orally for every 50 kilograms of fish, and the fish were mixed and fed once a day.

After more than 20 days of breeding, when the length reaches 4 to 6 centimeters, they will be screened and raised in pools according to size. The stocking density is generally 2,500 to 3,500 fish per acre, and the water depth is more than 1.5 meters. Keep the pool water at a suitable fertilizer level. It is appropriate to have a transparency of 30 cm and an oily green water color. Feed twice a day. The main feed is minced surimi and floating pellet feed. Vitamins B and C should be added to the feed. The daily feed amount is 6% of the fish body weight. Feed the mixture of oxytetracycline, erythromycin, and vitamin drugs twice a month for 3 days each time. At the same time, regularly spray and disinfect the entire pond with 0.4 international units of strong chlorine or 20 international units of formalin. . Do a good job of patrolling the pond every day, and turn on the machine to increase oxygen when the air pressure is low at night. If the pond water deteriorates, drain and change the water in time to keep the pond water fresh.

After the seedlings are released, sufficient oxygen should be used. It is best to use the bottom of the diffusion stone to increase oxygen. Generally, no feed is added on the first day. Feeding and training will gradually begin after one day. It is required to set the time, usually 4 meals. The best food for the opening is water spider. You can also mix fish paste with part of the eel feed for the opening. When the fry are 5 to 6 centimeters, you can gradually feed them puffed food. Anti-enteritis drugs should be appropriately added to the feed during the fry stage. The grid will grow as the fry grow. Gradually dismantle.

3. Strengthen daily management

When the adult fish are about 10 centimeters long and are put into ponds for adult fish breeding, the survival rate is high. The stocking specifications should be neat to avoid cannibalism. , the appropriate stocking density is 1,000 to 1,500 fish per mu, and at the same time, 40 large-sized bighead carp species, 20 silver carp species, and 200 Pengze crucian carp are cultured to make full use of the water body, regulate water quality, and increase production.

The temperature is suitable from September to October, which is the stage of rapid fattening of bass, so water quality adjustment cannot be ignored.

The disinfected pond is filled with fresh water through a filter. The water depth is about 80 centimeters, and part of the compound fertilizer is applied to cultivate plankton. Bass is a bottom-dwelling fish that likes to live in clean water with high dissolved oxygen content (4 to 6 mg per liter and a transparency of 30 to 40 cm). New water should be added flexibly and timely according to the water color and transparency. In the early stage, because the fish are small and the temperature is low, the water quality is easy to control, and the cycle of adding water and changing water can be longer. As the fish body grows and the biomass of the fish pond increases, the pond should be patrolled frequently, new water should be injected frequently, and the aerator should be used rationally to increase oxygen.

Feeding should be "fixed, timed and quantitative". Generally, 2 meals are fed a day, at 6 to 7 o'clock in the morning and 6 to 7 o'clock in the evening. A bait bridge should be built in the pond. , it is advisable to feed the baby normally until he is 80% full at each meal. In case of high temperature or cooling, the amount of feeding should be appropriately reduced. Pay attention to the feeding and health status of the fish every time you feed, so that contingency measures can be taken in time. The water quality should be kept fresh and the dissolved oxygen should be sufficient. If the breeding density is too high, a large amount of residual bait and excrement will easily remain at the bottom of the pond. The decomposition concentration of harmful substances will be high, which will consume a large amount of oxygen in the water. As the fish grow older, the number of times the oxygen machine is turned on can also be appropriately increased. Apply biological agents to effectively degrade ammonia nitrogen and nitrite and maintain good water quality. In the evening, especially at 2 to 3 o'clock in the middle of the night, the operation of the aerator should be inspected.

4. Scientific prevention of epidemic diseases

Bass likes to overeat and are prone to enteritis. During the day, the increase or decrease in food intake of bass should be observed to judge its health status. The abdomen of the sick fish is enlarged, the anus is red and swollen, and light yellow mucus flows out when the abdomen is squeezed. This is caused by feeding spoiled feed or excessive feeding. The amount of feed should be appropriately controlled to help reduce costs, avoid contaminating water quality, and reduce the occurrence of gastrointestinal diseases. During treatment, the feed should be reduced first, it is best to stop feeding for one meal, and the disease can be cured by feeding it with Guangpu antibiotic mixed with bait for 3 to 5 days. At the same time, check whether there are fish swimming in the water. Generally, there will be a small number of fish swimming in the water before a large number of illnesses occur. This is the best time for medical treatment and medication, and it is also a critical period for prevention.

Hepatobiliary syndrome is prone to occur in autumn, with the main symptoms being a decrease in food intake, fish swimming gradually and unknown deaths. The main reason is that under high-density culture, drugs are frequently released, and toxic and harmful substances in the water body slowly accumulate in the fish body, leading to fish organ dysfunction and tissue damage. Or long-term overfeeding, long-term overload of the fish liver leads to metabolic disorders and metabolic disorders. The water environment should be well controlled and fed scientifically. Regular feeding with some liver-soothing and choleretic Chinese herbal ingredients will have a certain preventive effect.

Autumn is prone to parasitic diseases, so disinfection and insecticide work should be carried out. Generally, disinfection is done every 15 days. The frequency depends on the feeding status of the fish. Parasitic diseases mostly occur on the body surface and gill filaments of fish in the intermediate breeding stage. They are characterized by weight loss, blackening of the body color, and erosion of the mouth end. Generally, parasites can easily cause secondary bacterial infections, so disinfection is generally required after killing insects. Water changes are often used to improve water quality for prevention. For treatment, a mixture of copper sulfate and ferrous sulfate (5:2) of 0.77 to 1 mg per liter can be sprayed evenly throughout the pond, or 20 to 25 mg of formalin per liter can be sprayed throughout the pond.