THE FEATURES OF SHEEP ADAPTATION TO THEIR KEEPING IN MOUNTAINOUS CONDITIONS

A significant amount of precipitation is the main obstacle to the promotion of cultivated sheep breeds in mountainous conditions. In scientific literature, there are individual authors’ statements that such sheep in the mountains feel oppressed. As a result of heavy rains their fleece quickly gets wet, and than gets dry for a long time. That is why sheep become heavy and often die of colds. On mountain pastures it is often observed that sheep with thin and semi-thin wool stand motionless and helpless in the rain, and sheep with half-rough and coarse wool continue to graze even in the rain. These observations served as the basis for experiments on the adaptability of sheep in mountainous conditions. The scientific-production experiments were conducted in distant-mountain maintenance of the Republic of North Ossetia-Alania. Under the experience were fine-Tushino hybrids with different types of wool and fleece structure. The first group was formed from the ewes with fine wool and staple fleece structure; the second group consisted of the sheep with semi-thin wool and staple-braid structure of fleece; the third group consisted of the sheep with semi-rough wool and staple-braid structure of fleece; the fourth group consisted of the sheep with the braid structure of fleece. The skin and the wool were taken of all the experimental ewes before the start of the experiments. The studies on the morphology of the skin were carried out according to the method of Diomidova N. A. Panfilova, E. P. and Suslina E.S. It is found that the different fleece structures in sheep are due to the differences in the structure of the skin, location of the follicles in the skin, their size and density. There is the highest density of hair follicles in the group of animals, having staple fleece structure, they have a less depth and length of hair follicles and thinner skin compared to the sheep, which have braid and staple-braid fleece structure. The nature and the duration of water runoff, as well as the drying time of the sheep’s wool with various fleece structure are different. In sheep with braid and staple-braid fleece structure water does not penetrate deep into the fleece during precipitation, it flows intensively, a small amount of it stays in the wool cover and evaporates quickly. Water penetrates deep into the fleece and the skin of the sheep with a staple structure, and a significant amount of it stays in their fleece. Key words: fleece, staple structure, braid structure, staple-braid structure, skin thickness, skin layers, follicles