THE INFLUENCE OF THE TYPE OF WOOL COVER AND FEEDING CONDITIONS DURING THE GESTATION PERIOD OF EWES ON THE MORPHOLOGICAL PARAMETERS OF THE SKIN OF THE OFFSPRING

The skin is an indicator of the body type and is a mirror reflecting the processes occurring in the animal’s body. To determine the effect of feeding conditions and the type of wool cover of ewes on the skin morphology indicators of the resulting offspring, studies were conducted in the foothills of the North Caucasus in 2021-2023 on fine-fleeced Tushino crossbreeds with fine and semi-fine wool during the mating period. The control groups received a moderate type of feeding according to the standards of the All-Russian Society of Veterinary Genetics (2003), and the experimental groups received an intensive type of feeding 15 % higher than the All-Russian Society of Veterinary Genetics standards for overall nutritional value. Skin samples from five lambs from each group were taken at birth, at the age of 5, 14 and 18 months in the flanks by biopsy. It was found that from 5 to 14 months of age, there is a slight decrease in the overall skin thickness. Thus, in the fine-wool ewes of the experimental group it decreased by 49.98 µm, or 2.3 %, and in the control group by 171.36 µm, or 8.2 %. In the semi-fine-wool ewes this decrease was equal to 2.3 and 3.8 %, respectively. At the age of 14 to 18 months, there was an increase in both the main layers of the skin and its total thickness. At birth, 45.5 % of secondary follicles in the fine-wool lambs of the experimental group produced wool fiber, and 37.8 % in the control group. In the semi-fine-wool lambs, the percentage of producing fibers was equal to 42.1 and 39.2 %, respectively. By the age of 5 months, all follicles in the fine-wool lambs of the experimental group produced wool fiber, and in the control group, 97.6 % of follicles were in the fiber stage. In semi-fine-wool ewes, they were 98.7 and 92.4 %, respectively. At 14 months of age, all follicles of the experimental fine-wool and semi-fine-wool lambs produced wool fiber, while in the control lambs, they were 98.7 and 98.6 %, respectively.