Effect of sex on histological and histochemical structures of interdigital sinus in adult Bakhtiari sheep of Iran

The aim of this study was to investigate the effect of gender on the histological and histochemical structures of various anatomical regions of the interdigital sinus in the Iranian native sheep. Tissue samples from different anatomical regions of each sinus were obtained from 15 female and 15 male adult Bakhtiari sheep. The sections stained with H&E, Periodic acid- Schiff, Alcian blue, Verhoeff’s, Masson’s trichrome, and Gomori’s method. The sinus was covered by skin and fibrous capsule. The sinus contained descending part, flexure, ascending part, excretory duct and orifice. The sebaceous glands were simple branched acinar and the sweat glands were simple coiled tubular type. The secretory caps were observed in the secretory cells protruded into the lumen. The various histological and histochemical structures of the interdigital sinus showed no considerable differences among various anatomical regions of the right and left sinuses. Also, no significant sex-based differences were found. The surface epithelial cells of the apocrine glands and their secretion contained both neutral and acidic glycosaminoglycans. It is concluded that the general histological and histochemical structures of the interdigital sinus in Bakhtiari sheep were similar to those of other native sheep, but there were also some differences.