Culture techniques of freshwater perch

From the living habits of bass, we can know that perch can live not only in sea water, but also in fresh water, so it is called freshwater bass. The focus of freshwater sea bass culture is also culture technology, so it is very important to master culture technology.

Culture techniques of freshwater perch

I. Pond construction

1. Choose places with rich water sources and fresh water quality to build ponds.

2. Each pond is 5-8 mu, which is rectangular, and the north-south direction is better.

3. It is required that the bottom of the pool is flat, the sand and mud bottom is fine, the bank of the pool is firm and the depth of the pool is 2 meters.

4. The bottom of the pool should be buried with drainage pipes. At the same time, it is equipped with 1 to 2 1.5 kilowatt aerators, and the farm should have backup generating units.

5. To do a good job of desilting and disinfecting the pond before stocking, you can sprinkle disinfection with 50 kilograms of quicklime or 5 kilograms of 10 kilograms of bleach per mu a week before stocking.

6. Fertilize the basic bait of the pond water before releasing seedlings to make the pond water oil-green or tea-brown.

2. Feeding and management

The main results are as follows: 1. The perch seedlings are sifted and raised in ponds according to size.

2. The stocking density is generally 2500 ~ 3500 tails / mu. Water depth of more than 1.5 meters, to maintain the appropriate fertility of the pool water, transparency in 30 cm, water color is oil-green is appropriate.

3. Twice a day, the main feed is minced surimi and floating pellet feed, vitamins B and C should be added to the feed, and the daily feeding amount is 6% of the body weight of fish.

4. Earth mold poison, erythromycin and vitamin drugs should be fed twice a month for 3 days each time.

5. At the same time, sprinkle and disinfect the whole pond with 0.4ppm strong chlorine or 20ppm formalin regularly.

6. do a good job in pond patrol management every day, turn on the machine to increase oxygen at night or when the weather is hot and pressure is low, and find that the pool water should be discharged and changed in time to keep the pool water fresh.

Living habits of freshwater perch

Sea bass is omnivorous fish, like to eat small paste leaf fish, small yellow croaker, small squid, cuttlefish, sea shrimp, squid, sand silkworm, knife fish, earthworms, sea cockroaches, rock worms, grass insects, silkworm and so on. The sea bass has a long silver-gray body, a large mouth and a flat jaw, and there are small black spots on both sides of the dorsal fin, which inhabit the coastal sea. it is ferocious and likes to chase and prey on small fish, sea shrimps and drooping insects. The maximum weight of the fish can reach 20 to 30 kilograms; the number of eggs laid by it is about 100 million; the sea bass is delicate and fat, with few spines and more meat without fishy smell, so it is a valuable edible fish.

Perch is a pelagic fish, ferocious, fast, can prey on a variety of small sea fish and shrimp. Fishing waters can be chosen in offshore bay waters. Among them, there are many in the Yellow Sea and Bohai Sea, and it is a good season for sea bass fishing from May to October every year, and autumn is the golden season for perch fishing; when the weather turns warm in spring, the perch leaves the deep water and forages in the estuary and bay; after the Beginning of Summer. Sea bass like to go to the sea near the estuary to lay eggs, forage and fattening.

Seedling cultivation of freshwater sea bass

1. Temporary cultivation of seedlings: the sea bass seedlings caught from the sea area (body length 1.5-2 cm) should be desalinated to 4-7 ‰ before putting into the temporary culture pond (salinity 1 ‰). The natural sea bass seedlings in the northern sea area are the best. Due to different physical and chemical factors, the seedlings grow fast and the individual is large, which can shorten the culture cycle and increase economic benefits.

2. Feeding management: the stocking density of the temporary pond is controlled at 10-20,000 per mu, and the pond should be flushed to increase oxygen frequently. On the second day of the lower pond, fresh baits such as zooplankton and red worms are fed, and the fish paste, floating particles and fresh baits are mixed and fed slowly, and gradually domesticated to feed minced surimi and floating pellets. The daily feeding amount is 15% of the body weight of the fish.

3. Seedling disinfection: during the temporary breeding period, sprinkle and disinfect with 0.3ppm strong chlorine or 15ppm formalin once a week. Three days before the start of baiting, every 50 kg of fish should be fed with 0.5g of dysentery, 3g of oxytetracycline and C1g of vitamins, once a day for 3 days. After more than 20 days of feeding, the fish growing to 4-6cm can be reared in large ponds.

Prevention and treatment of common diseases of freshwater perch

1. White candle disease of eyeball

Symptoms: eyeball white candle disease is more common in spring and summer fish fry stage, the eyeball appears white spot, gradually expand to cover the whole eyeball, serious exophthalmos fall off, which can be caused by fresh bait and vitamin deficiency.

Prevention and control methods: renew the aquaculture water body, feed fresh bait, add vitamins (especially vitamin B).

2. Water mildew

Symptoms: flocculent bacteria appeared in the fish, diseased fish swam slowly on the surface, lost appetite, emaciated and died, mostly caused by infection after fish injury.

Prevention and treatment methods: replace new water, maintain good water quality, dissolve malachite green with 6 × 10-6 malachite green for 5-10 minutes.

3. Skin ulceration

Symptoms: most common in high temperature season, fish local descaling, hyperemia and ulceration, mostly caused by bacterial infection caused by fish injury, diseased fish loss of appetite, floating slowly swimming, emaciation and death.

Prevention and treatment: 20 × 10 ~ 6 chloramphenicol (or furacilin) bath for 4-5 hours.

4. Enteritis

Symptoms: abdominal distension, anal redness and swelling, yellow mucus outflow, weight loss, loss of appetite, severe death, caused by food deterioration and high diet fat.

Prevention and treatment: furazolidone bait was prepared with 0.1% addition and fed continuously for 5-7 days.

5. Fish lice disease

Symptoms: fish body parasitic fish lice, sick fish swimming restless, friction against the pool wall, heavy fish body emaciation and death.

Control method: sprinkle the whole pool with crystal trichlorfon to make the water content up to 0.25 × 10 ~ (- 6)-0.3 × 10 ~ (- 6). Once every 3 days, the medicine can be cured twice, and the fish lice can also fall off by soaking in pure fresh water for 2-3 minutes.

6. Blackbody disease

Symptoms: the diseased fish are black and thin, do not eat, slow to respond, and often dissociate on the surface of the water. From April to June, seedlings with a body length of less than 10 cm are easy to be infected with the disease.

Prevention and control methods: there is no effective control method, seedling quarantine should be strengthened, diseased fish should be isolated and destroyed in time.

After understanding the technology of freshwater sea bass culture from the above, farmers should begin to choose good quality seedlings, and then begin to cultivate seedlings. When cultivating seedlings, they should pay special attention to the feeding of seedlings. If the feeding is not in place, it will lead to slow growth of seedlings. Of course, when the sea bass is cultured in fresh water, the sea bass will inevitably get sick, so it is necessary for farmers to carefully observe the condition of the sea bass and take timely measures.