Because cotton and goats have been bred for thousands of years, they are physically strong, their hairs are thick, their thermal conductivity is low, and their surface heat dissipation is slow. Therefore, they are mostly afraid of heat and not afraid of cold. They like to take a rest in a dry and ventilated place and rarely suffer from it. Disease, non-critical illness does not show pathology. Individual sheep breeds also have particularly strong adaptive abilities. For example, Tibetan sheep in the Qinghai-Tibet plateau have good anti-cold Tibetan sheep, and on the other side of the Taihu Lake, there are lake sheep that can adapt to moist feeding. Cotton and goats can tolerate seasonal changes in nutrition. When the summer and autumn seasons are warm and the pastures are plentiful, sheep can quickly use the grazing land in a short period of several months. Not only does the body weight grow faster, but it also accumulates in large numbers. fat. For example, the average weight of Xinjiang fine-wool sheep increased by about 10 kg in June-October, up to 25 kg. In Qingcao period, Hebei Big Tail Han sheep not only gains weight quickly, but also accumulates large amounts of fat (up to ten kilograms) in the tail. In winter and spring withered grass, tail fat is gradually consumed to ensure its smooth transition. Overage period