ARRANGEMENT OF ELASTIC FIBERS IN THE INTEGUMENT OF DOMESTICATED MAMMALS

The hairy skin of important domesticated mammals (12 species) was stud ied with scanning election microscopy, transmission electron microscop y, laser scanning microscopy, and several light microscopical methods, to obtain more information about three-dimensional elastic fibre arra ngement. It was obvious that there is a basic construction scheme of t he elastic fibre meshwork as present in the upper and mid-dermis, with special regard to the size, number, and grouping of hair follicles. I n the densely-haired species, in particular, a typical elastic mat wit h horizontal fibres is formed. In many of the sparsely-haired animals, the upper and mid-dermis show a sponge-like elastic system. In the ra ther massive, collagen-rich skin of large species, the lower two third s of the dermis without hair follicles only possess a loosely-structur ed elastic network, but thick elastic sheets are found at the border z one with the hypodermis. Specific features appear with regard to the t ype of mechanical strain exerted, different body regions, varying hair follicle density, or as connected with the anchoring of the hair foll icle complex, blood vessels, and nerves.