What are the species of grouper? What are the main points of breeding?

Grouper is a kind of large and medium-sized marine fish, mainly distributed in coastal areas, its meat is delicate, nutritious, eat like chicken, deeply loved by people, and now most of the market is farmed. What are the species of grouper? What are the main points of breeding?

What are the species of grouper?

1. East Star spot (common in Hainan)

The colors of the East Star spot are blue, red, brown and yellow, etc., with a slimmer figure and a small head than ordinary grouper. There are black pupils in the blue eyes, and the body is covered with white tiny flowers, similar to the stars in the sky, so it is called "star spot". As for the word "east", it comes from Dongsha Islands in eastern China.

2. Gem grouper

Gem grouper generally has a body length of 25 cm to 30 cm, and its body surface and fins except pectoral fins are covered with gem-like spots. There are red stripes on the pectoral fin, the caudal fin is shallowly concave and the edge is white. It is a warm-temperate middle and lower layer fish, mostly living in the reef bottom sea area, with sexual transformation, first female and then male. The growth is relatively slow. Grouper ferocious, alert, mainly meat, like to eat fish, shrimp, crabs, do not like to group, when hungry, there is a phenomenon of cannibalism. Gem grouper is distributed in the Indian Ocean and the western Pacific Ocean, and in the South China Sea in China. Artificial cage culture has been carried out in many provinces of our country.

3. Grouper

There are several orange-red spots in the lower part of the body and six dark brown vertical stripes on the side of the body, with the widest interval between bands 3 and 4. Only the caudal fin is spotted. Warm water middle and lower layer fish. Larvae and juveniles feed on plankton, while adults feed on fish, shrimp and crabs. Female and androgynous, the female fish first matured, the body length was 250 mm ~ 400 mm, and the male fish matured completely at 6 years old (some 5 years old). The absolute fecundity is 80 000 ~ 250000 eggs, the spawning period is from late May to July, 20 ℃ begins to lay eggs, 22 ℃ ~ 24 ℃ peak period, floating eggs are laid. The water temperature is 22 ℃ ~ 25 ℃ and it takes 23 hours to 30 hours to hatch the larvae. The meat is delicious and is a valuable fish. live fish are sold in large quantities to Hong Kong and Macau. It is the object of shallow sea culture in China and Southeast Asia, and can be cultured in cages. Distributed in Taiwan, East China Sea, South China Sea, and Japan.

4. Spotted grouper

The snout of Epinephelus punctatus is short and blunt, the dorsal fin has 8 ~ ll root spines, there are no black spots at the base, there are 5 indistinct transverse bands on the side of the body, and spots are scattered on the side of the body and on each fin. It is a tropical middle and lower layer fish, likes to inhabit the rock reef bottom sea area, and is a valuable fish in the South China Sea. Sexual ferocious, meat-based, like to eat fish, shrimp, crabs, when hungry to kill each other. It can live in the waters of salinity 11 ‰ ~ 41 ‰, the optimum water temperature is 22 ℃ ~ 28 ℃, the appetite is decreased below 18 ℃, and the fish below 15 ℃ is out of balance. Cage culture can be carried out. Distributed in the East China Sea, South China Sea and other waters.

Second, what are the main points of grouper culture?

1. Seedling selection

Parent fish can be farmed with adult fish or caught in natural sea areas. The female fish weighs 5kg-8kg and the abdomen is dilated and soft, while the male fish weighs more than 8kg and gently presses the abdomen to drain semen. According to the proportion of 3 ∶ 1-8 ∶ 1, male and female parent fish are cultured or temporarily cultured in indoor cement ponds. Through artificial intensive cultivation, daily water change and pollution absorption, parent fish can be naturally spawned and fertilized without hormone stimulation, and high quality fertilized eggs can be obtained.

2. Daily management

Choose a reasonable density of cages and fish rafts to prevent the occurrence of hypoxia accidents. In addition to baiting, the growth, feeding, activity and body color of the fish should be regularly observed and checked, as well as whether the cage is damaged, the number of attached organisms, and regularly remove the fouling organisms attached to the cage, so as to maintain the smooth flow inside and outside the cage, regularly monitor the water quality and protect the culture environment. The monitoring of aquaculture water according to the first kind of sea water quality standards promulgated by the state is conducive to the normal growth and delicious meat quality of grouper and prevent accidents caused by the deterioration of water quality.

3. Bait feeding

Under normal circumstances, some food organisms such as rotifers and copepod nauplii should be kept in the pond to feed the larvae. Check the biological feed density in the pond water three times a day in the morning, in the middle and down. If it is found that the biological bait density is insufficient, it can appropriately supplement biological bait such as rotifers and copepods to keep the biological food in the pond sufficient. If there is no biological bait, you can properly sprinkle with bait such as spirulina powder, Prawn Crackers, etc. (according to the size of the fish fry, use 200 million 80 mesh sieve to filter and feed) to reduce the self-harm of fish fry and improve the survival rate of fish fry.

In the later stage of breeding, appropriate amount of minced fish and shellfish can be added, or 0.15~0.3ppm powder formula feed can be fed directly. The feed density was checked for 2 to 3 times a day, and the feeding amount was determined by the fullness of the fry.