The main indicators of the histology of the skin of fine-fleeced sheep breeds of the Stavropol Territory

Comparative characteristics of skin histology indicators of fine-fleeced breeds of sheep of Stavropol have been presented. The skin and wool cover of sheep are a single whole. The skin has a protective function, it is involved in thermoregulation and metabolism. According to the condition of the skin and wool cover of sheep, one can get a certain idea of their breed affiliation. In this regard, scientists from the laboratory of morphology and product quality of All-Russian Research Institute of Sheep and Goat Breeding – a branch of the North Caucasian Federal Scientific Agrarian Center have been studying skin histostructure indicators (hair follicle density and skin thickness) on animals of different sex and age groups of fine-fleeced breeds at 4.5 and 12 months of age. It was found that in sheep of Stavropol breed the total skin thickness at the age of 4.5 months was 2155.6 microns, and at 12 months it was 2258.5 microns, i.e. there was a thickening of 103.5 microns or 4.8 %. In sheep of Soviet Merino this thickening was 73.3 microns or 3.3 %, Manych Merino it was 130.9 microns or 6.4 %, Grozny breed it was 157.1 microns or 9.2 %, Caucasian breed it was 158.3 microns or 6.7 %. Follicle density decreased with age, but the ratio of secondary follicles/primary follicles almost did not change and remained constant. According to our data, the total density in Stavropol breed was 96.95 microns at 4.5 months of age, and 92.60 microns at 12 months of age, i.e. decreased by 4.7 %. In sheep of breed Soviet Merino density of follicles decreased by 5.9 %, Grozny breed by 2.9 %, Manych Merino by 6.1 %, Caucasian breed 7.6 %. At the present stage, when merinos of a new type have been bred, which have a high living weight and thin coat, and in which the correlation between these indicators practically does not work, it is necessary to further study the skin histology to identify animals that combine high meat and wool productivity.