Morphofunctional characteristics of the skin in the assessment of adaptive capabilities in wild boars (sus scrofa scrofa (l., 1758)

The study of the mammalian skin reveals a wide range of adaptations of animals and their organs to various conditions of existence.
The aim of the work is to establish, on the basis of factual material, the morphological and functional features of the skin of wild boars (Sus scrofa scrofa (Linnaeus 1758)) in conditions of adaptation to adverse natural and climatic factors.
The skin samples of 6 adult individuals (males) of wild boar (Sus scrofa scrofa) caught in the autumn-winter period were studied. The morphometric parameters of the skin layers and their components were measured, based on the primary data, the total thickness of the skin and epidermis, the ratio of the outer and inner layers of the epidermis were calculated. The established absolute values of indicators (microns) were converted into relative values (%), the ratio of the stratum corneum and the underlying rows of the epidermis was found. The results obtained were processed using the Statistica (6.0) software package.
In the studied animals, the skin is quite thick, with a wide variability of the indicator. We noted a well-developed epidermis in the skin of wild boars, its thickness averaged 72.99 microns. The stratum corneum, on average, reached a thickness of 36.13 microns (44.75-56.65% of total epidermis thickness), with a low level of variation (8.58%), which may be genetically deter mined. The dermis of the wild boars’ skin is well developed; it consists of densely packed, medium-sized bundles of collagen fibers that form ties with a heterogeneous binding, which indicates a high density and strength of the skin under mechanical stress and, possibly, is associated with sexual characteristics (the ability of the skin to withstand blows during fights) . Inclusions of adipose tissue were found in the lower layers of the dermis.
The sebaceous glands are large, well developed, actively functioning in winter (as evidenced by the lipid mantle of the stratum corneum). A significant level of group variation was established, due to the wide individual variability of the indicators of functionally active structures (skin glands) in the studied animals, while the indicators of other derivatives of the epithelium – hair follicles, were distinguished by a very low level of variability.
The data obtained allow us to conclude that the variability of the skin structure and its derivatives in wild boars have a certain significance in the process of adaptation to the effects of adverse climatic conditions, depending on the season of the year.

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