Histomorphological, Histochemical and Histoenzymic Studies on the Dermis of Skin of Goat (Capra hircus)

Background: Skin is a versatile organ, which is extremely important for protection, perception, water regulation and wound healing. The skin of goat is considered extremely durable used by the tannery Industry to make rugs and carpet binding.Methods: The present study was conducted on the skin of goats of either sex to study the age wise changes in the histomorphology, histochemistry and histoenzymology of dermis. The skin samples were collected from Nagpur Muncipal Corporation Slaughter house immediately after natural death and subsequently processed and stained for histological, histochemical and histoenzymic studies. The total of 220 samples, 20 each from different body regions namely dorsal neck, lateral neck, ventral neck, dorsal thorax, lateral thorax, ventral thorax, dorsal abdomen, lateral abdomen, ventral abdomen, lateral thigh and medial thigh were collected. The animals were divided into two groups, viz. six to twelve month of age (Gr I) and above one year age (Gr II).Result: It was observed that the dermis was composed of collagen, elastic, reticular fibers, cells of connective tissue, blood vessels, nerves, hair follicles, sweat glands, sebaceous glands and arrector pili muscles in all body regions in Gr I as well as in Gr II. The dermis was divided into thin superficial papillary layer and a thick deep reticular layer. The dermal papillae were the upward projections of superficial papillary layer between epidermal pegs. In reticular layer, fibroblasts were larger, while in papillary layer, fibroblasts were thin long, compressed and spindle shaped. The collagen fibers were more in number as compared to other fibers in dermis and they were densely arranged in papillary layer and parallel with the skin surface below the epidermis. The elastic fibers were present in between the collagen fibers around the blood vessels and hair follicles. The arteriovenous shunt was found surrounded by capsule of connective tissue consisting of smooth muscle cells. The more number of hair follicles at deep part of papillary layer and few follicles were present in reticular layer. The hair follicle composed of outer root sheath, inner root sheath, cortex and medulla. The depth of primary hair follicle increased with the advancement of age. Moderate PAS positive activity was noted in the papillary layer, while it was weak to moderate in reticular layer. The reticular layer of the dermis showed moderate Sudan black B activity for the presence of lipid than the papillary layer. The mild acid phosphatase activity was seen in the papillary and reticular layer of dermis, while moderate acid phosphatase activity was noticed in the blood vessels. A mild alkaline phosphatase activity was present in dermis in Gr I and Gr II. Conclusion: The present study would form a baseline data on the histomorphology, histochemistry and histoenzymology of skin of goat which would be helpful in future research prospective.