Introduction of White Crucian Carp

White crucian carp, also known as Japanese crucian carp, large limit crucian carp, Hanoi crucian carp and so on. Because the white crucian carp has the advantages of wide diet, rapid growth, large size, high water starting rate and less diseases, it can grow, mature and lay eggs well in all kinds of fresh water bodies in China. It has been widely popularized in many provinces and cities in China. 1. The white crucian carp originated from Lake Biwa, which has a long history in Japan. In about 1897, a fisherman in Hanoi Prefecture, Osaka Prefecture moved it into inland rivers and ponds to raise it. After years of training and careful breeding, a pure line of fine varieties was obtained, hence the name Hanoi riveting. In March 1976, Guangdong was introduced from Japan and raised on a trial basis. In February 1977, according to the silver-white body color of Carassius auratus and its feeding habits, Gill rake structure and habits were similar to silver carp, so it was named "white crucian carp" in Chinese. 2. The white crucian carp is silver-white, large, tall and flattened on the side, the front back is like a hump, the head is slightly smaller, the tail stalk is slender and the mouth crack is larger. The body length is 2.1 times of that of body height, 32 lateral scales, 120 Gill rakes, and many branches and spines on the inner side of Gill rake, forming a reticular structure. White crucian carp is an omnivorous fish mainly composed of phytoplankton and other plant bait. In the early stage of fry stage, zooplankton is the main food, mainly rotifer. Later, he began to eat phytoplankton. The main stage of diet transformation is when the body length is 15ml / 25mm. In the fish species and adult stage, white crucian carp take floating plants as the main food, and also eat a certain amount of organic detritus and aquatic insects. White crucian carp likes to live in the middle and upper layers of the water body and has a strong tolerance to changes in water quality and low dissolved oxygen. In a body of water with a dissolved oxygen content of less than 0.2 mg per liter of water, it can survive for several hours, causing death only when it is less than 0.1 mg / L. It also has a wide adaptability to temperature and can feed and grow normally all the year round. In the case of natural waters or artificial culture, the growth rate of white riveting is significantly faster than that of ordinary crucian carp. In the water body with good growth conditions in southern China, the white crucian carp can reach sexual maturity at the first winter age, and its reproductive habits are similar to those of common carp and crucian carp. it is a normal diploid sexual reproductive population and can reproduce naturally in still water. In natural waters, spawning begins when the water temperature reaches more than 17 ℃. The optimum water temperature for spawning is about 20 ℃, which belongs to the type of laying eggs in batches.