Assessment of wool density of fine wool sheep at an early age

Abstract

The article presents data on the study of the morphology of skin cover and
coat in the age aspect, correlations of the main indicators of wool productivity and histologi
cal structure of the skin. The skin of sheep is the most studied in comparison with other types
of farm animals. The order and characteristics of the formation of the skin cover and coat in
the embryonic and postembryonic periods, the effectiveness of various influences on this process, the correlation between skin and wool in adult animals and the importance of skin quality indicators in selective breeding are known. Such great attention to the issues of the structure and formation of the skin in sheep is explained by the fact that the quantity and quality of
the wool is closely correlated with the structure and function of the skin. The studies of the
skin cover and coat of sheep of the Stavropol breed in the collective farm “Rodina” of the
Apanasenkovsky District showed that the follicle density per mm2 of the skin area is greater
in both young rams and young ewes at birth. On average, it decreases by 20.0% by weaning,
and 32% by the age of one year. The hair follicle / follicle density ratio in young rams at birth
was 12.9. In young ewes it was 11.7, which practically did not change with age. The papillary
dermis occupies 70.3% of young rams and 69.6% of young ewes. The average thickness of
the skin in young rams was 2104.99 microns. In young ewes, it was 2077.88 microns. On average, in comparison with the period at birth, it increased by 28.0%. Thus, as a result of the
studies, age-related changes in skin structure were established, both in young rams and young
ewes. The hair follicle / follicle density ratio is a breed trait and doesn’t change much during
the life of the animal, which makes it possible to evaluate them by the density of follicles at
an early age.