Tortoise generally refer to the purpose of turtles in a broad sense and the species of turtles in a narrow sense. In animal taxonomy, turtles belong to reptiles, turtles are one of the common turtles, but also the existing ancient reptiles. Chitosan is characterized by being covered with a very strong back shell (except turtles) that can attack the glans, tails and limbs. Most sea turtles are omnivores, such as worms, snails, shrimp and fish, and also eat the stems and leaves of plants. In addition to cold areas, turtles are also distributed all over the world. Turtles are distributed almost everywhere in China, but the output in the middle and lower reaches of the Yangtze River is relatively high, and it is also produced in all parts of Guangxi, especially in the southeast and south of Guangxi.