CATDOLL : CATDOLL: What are the varieties of Penaeus vannamei fry (and where is the distribution of Penaeus vannamei fry?)

The white shrimp is also commonly known as white-leg shrimp or white shrimp. It was once translated as Penaeus vannamei. It looks very similar to Chinese shrimp and Penaeus merguiensis. Its average lifespan is at least 32 months. The adult can be up to 24cm long, with a thin carapace. Its normal body color is light blue-gray, without any markings on the body. Its legs are often chalky, so it is called white-leg shrimp.

Current status of Penaeus vannamei farming:

Penaeus vannamei is one of the three largest shrimp species in the world. Penaeus vannamei is native to the Pacific coast of South America. Professor Zhang Weiquan of the Institute of Oceanology of the Chinese Academy of Sciences took the lead in introducing this shrimp from the United States and broke through the seedling barrier in 1992. From small trials to pilot tests, it has been promoted throughout the country. The provinces and autonomous regions of Jiangsu, Guangdong, Guangxi, Fujian, Hainan, Zhejiang, Shandong, Hebei and other provinces and autonomous regions have gradually promoted the cultivation. The Penaeus vannamei cultivated in Yangjiabo Town, Hangu District, Tianjin is world-famous and has the reputation of "China's Fish and Shrimp Hometown". Among them, the technology of Penaeus vannamei is the most mature.

Physical characteristics:

The white shrimp looks like Chinese shrimp, with a normal body color of light gray, thin shell and fat body, tender meat, meat yield rate of more than 65%, rich in nutrition, and is popular in domestic and foreign markets. The length of the tip of the frontal horn of white shrimp does not exceed the second section of the first antenna handle, and its tooth type is 7-9/1-2; the cephalothorax is short, and the ratio with the abdomen is about 1:3; the side hook of the frontal horn is short and disappears below the stomach thorn; the cephalothorax has liver thorns and gill horn thorns; the liver thorns are **; the first antenna has two whips, the inner whip is thinner than the outer whip, the length is roughly equal, but both are short (about 1/3 of the length of the first antenna handle); the upper limbs of the 11th to 3rd pairs of walking legs are very developed, the 4th to 5th pairs of walking legs have no upper limbs, and the 5th pair of walking legs have rudimentary external limbs; the 4th to 6th segments of the abdomen have dorsal ridges; the tail segment has a central groove, but no marginal lateral spines.

Distribution range of Penaeus vannamei:

It is mainly distributed in the tropical waters along the Pacific coast of the western United States, from the Gulf of Mexico to central Peru, with a higher concentration in the waters near Ecuador. It is one of the three most productive varieties in the world. The shell of the white shrimp is thin, the normal body color is blue-green, and there are no spots on the body. Its morphology is similar to that of the Chinese shrimp (Penaeus chinensis); it naturally inhabits the sea area with a depth of 0-70m, is omnivorous, has three characteristics: strong adaptability, fast growth rate, and strong disease resistance. It can grow as long as the protein ratio in the bait accounts for more than 20%; it has delicious meat, high meat yield, wide salt tolerance, and high temperature resistance. Its seedlings can grow into adults after more than 100 days of cultivation, and the body length can reach 24cm.

Living habits:

The white shrimp has a thin shell and a fat body. It has delicious meat, high meat content and rich nutrition. The white shrimp has strong adaptability. Its natural habitat is muddy seabed with a water depth of 0~72m. It can grow in waters with a salinity of 0.5~35‰. The salinity tolerance range of 2~78‰ for juvenile shrimps of 2~7cm is 2~78‰. It can survive in waters with a water temperature of 6~40°C. The water temperature for growth is 15~38°C, and the optimal water temperature for growth is 22~35°C. The maximum temperature tolerance is 43.5°C (gradient range>), and the adaptability to low temperature is poor. When the water temperature is below 18°C, its feeding activity is affected, and it lies on its side at the bottom of the water when the water temperature is below 9°. It requires fresh water quality, dissolved oxygen content of more than 5mg/u, and the lowest dissolved oxygen content it can tolerate is 1.2mg/L. It can survive out of water for a long time and can be transported over long distances. The adapted pH is 7.0~8.5, and the ammonia nitrogen content is required to be low. It can live in seawater, brackish water and fresh water. The newly hatched planktonic larvae and shrimps feed and grow in the low-salinity waters (4~30%) in the shallow seas near the estuaries with rich bait organisms and the soft mud bottom of the coastal lagoon. When the average body length reaches 12cm, it begins to migrate to the offshore. The large-scale migration occurs at the clearest point of a month, the same time as the full moon and the new moon. Under the breeding conditions, they generally stay still at the bottom of the pond during the day and become active after dusk.

In farming, whiteleg shrimp has the advantages of large size, fast growth, low nutritional requirements, strong disease resistance, strong adaptability to changes in water environmental factors, low requirements for feed protein content, meat yield of more than 65%, and long survival time out of water. It is an excellent variety for intensive and high-yield farming, and is also the shrimp species with the highest single yield among the three major farmed shrimps in the world.

Production performance:

The growth rate of Penaeus vannamei is fast, and it can be put on the market after 60 days of cultivation. It has a wide range of adaptability to salinity (0-40‰), and can be cultivated in pure freshwater, brackish water, and seawater. It can grow from natural sea areas to freshwater ponds, and each has its own growth advantages. It is resistant to high temperatures, has strong disease resistance, low nutritional requirements, and grows fast. It has strong adaptability to changes in water environmental factors, low requirements for feed protein content, a meat yield of more than 65%, and a long survival time out of water. It is an excellent variety for intensive and high-yield farming, and is also the shrimp species with the highest single yield among the three major farmed shrimps in the world. Penaeus vannamei has a thin shell and a fat body, delicious meat, a high meat content, and rich nutrition.