Price and culture method of freshwater grouper fry

Freshwater grouper is a fish of the family Sparidae, with fast growth, hypoxia tolerance, strong disease resistance and beautiful appearance, delicious meat and rich nutrition. It can be used as both commercial fish and ornamental fish. At present, its culture scale is getting larger and larger. It has gradually become a new species of freshwater culture. Let's take a look at the price and culture methods of freshwater grouper fry.

How much is a freshwater grouper fry?

The price of freshwater grouper fry is about 0.3-0.8 yuan, but the price varies greatly due to the specification, variety, quality, market and quantity of freshwater grouper fry. The total length of freshwater grouper larvae is 0.58-0.6 cm. The yolk sac disappears on the 6th day after hatching at 26-28 ℃, and the yolk sac can be cultured in the pond after one month of culture. The fry with a length of about 10 cm can be put into the pond during summer in Taiwan, and the maximum body weight can reach 1200 g after 6-8 months of culture.

The Seedling rearing of Freshwater grouper

1. Clear the pond and disinfect the pond: the soil pond is the best for the freshwater grouper fry culture pond. The area of each pond is 50 to 100 cubic meters, and the water depth is 1 to 1.5 meters. Drain the water from the pond before releasing the fry, thoroughly clean the pond with quicklime and fertilize the water quality, so that the fry can eat natural bait in the pond.

2. Fish stocking: freshwater grouper should first test the water before stocking. The requirements for stocking in the same pond are the same. The density depends on the bait, technical level and cultivation specifications, generally 100 fish / cubic meter. The fry should be soaked in salt water for 15 minutes before entering the pond.

3. Water quality management: the water quality of freshwater grouper fry is easy to be corrupted due to fertilization, feeding and other factors, so the water is changed every 3 to 5 days, and the amount of water each time is 1 × 4 of the pool water. Some aquatic plants can also be transplanted in the pond to purify the water quality and facilitate the concealment and feeding of fish fry.

4. Screening and breeding: when the growth specifications of freshwater grouper fry are quite different, because they have the habit of eating big and small, they should be screened and raised in time, and the fry in the same pond should strive for the same specifications, so as not to affect the survival rate of fry.

Culture methods of freshwater grouper

1. Pond arrangement: the bottom of the freshwater grouper culture pond is sandy, the surrounding sea area is not polluted, the area is about 7 mu, and the water depth must be more than one meter. Some water cylinders, tires or pebbles can be laid at the bottom, because freshwater grouper has the habit of drilling holes.

2. Fish fry stocking: when a small amount of freshwater grouper is mixed in the pond, there are about 22,50 freshwater grouper per mu of water surface. When the main fish is freshwater grouper, tilapia, grass carp, crucian carp and so on can be mixed cultured, and 150,200 freshwater grouper per mu of water.

3. Feed selection: the protein content of artificial formula feed for freshwater grouper is 35-40%, animal protein should be more than 25%, other plant protein raw materials can be added, and the general feed coefficient can reach 0.8-1.2.

4. Domestication of fish fry: when the freshwater grouper reaches more than 3 cm, surimi can be fed on the table. 2-3 days later, a small amount of artificial formula feed is mixed with surimi, and then the proportion of artificial formula feed is gradually increased until all artificial formula feed is used.

5. Feed feeding: the daily feeding amount of freshwater grouper is about 20% of the fish's body weight, usually 3 times a day, artificial compound feed or fresh and tender forage can also be fed during the feeding period. When there is not enough zooplankton in the pond, appropriate amount of topdressing is needed to cultivate zooplankton.

Disease prevention and control of freshwater grouper

1. Rotten tail disease

[harm] the fin base of diseased fish is congested, the caudal fin, ventral fin and pectoral fin are the most serious, the body color fades, local redness and swelling and ulcers on the side of the body, and the mortality rate is as high as 90% in severe cases.

[prevention and treatment] wash with tetracycline or oxytetracycline for 4-10 minutes each time for 2-3 times, or sprinkle with furazolidone in the whole pool, once a day for 3 days.

2. Gill rot disease

[harm] the gills of diseased fish are reddish, the ends of the gills are congested, the local Gill tissue is necrotic and white, and in severe cases, the tissue decays and the cartilage is exposed.

[prevention] the whole pool was sprinkled with sodium dichloroisocyanurate, and the whole pool was sprinkled with 1520kg quicklime at a water depth of 1 meter per mu.

3. White spot disease

[harm] irregular leukoplakia appeared on the body surface of diseased fish, and in severe cases, leukoplakia became one piece, and the mucus on the body surface and Gill increased, swimming slowly, dyspnea, and often floated on the surface.

[prevention and treatment] washing diseased fish with fresh water for 2 minutes can kill pathogens, or wash diseased fish with copper sulfate for 2 hours for 2 hours for 3 days.

4. Vibrio disease

[harm] the body color of diseased fish faded, and local redness, swelling and ulcers on the body surface mostly occurred from April to November, especially from April to June, with a mortality rate of more than 90%.

[prevention and treatment] soak with furacilin and other antimicrobials for 3 minutes, or oral fish and shrimp Zhuangyuan mixed with 35% into the feed for 5-7 days.