Anatomical development of the skin in foetuses of Red Sokoto goats (Capra hircus)

The prenatal development of the skin in Red Sokoto goats (RSG) is one of the critical aspect for fetal growth, influencing postnatal adaptation, thermoregulation, and protective functions. This study investigated the morphological changes in the skin of RSG at different gestational stages viz.: days 0–50 (1st term), 51–75 (early 2nd term), 76–100 (late 2nd term) and 101–150 (3rd term) using anatomical techniques. Samples were collected from the skin of the head, the dorsum, and ventral abdomen. Grossly, the skin transitioned from a delicate, transparent, and light pink structure in the 1st and 2nd terms to a firmer, darker, and more pigmented tissue in the 3rd term. Histological analysis showed progressive epidermal differentiation, with the formation of a basal layer and periderm in the first term, followed by the development of an intermediate layer and stratum corneum in the 2nd term, except in the dorsum. Hair follicle formation was initiated in the early 2nd term with the initial stages of hair bud and hair bulb formations. Regional variations were observed, with the head and dorsal skin showing earlier follicular development. Moreover, the epidermal thickness did not vary across the regions. Similarly, there was no significant difference in the epidermal thickness in the male and female counterparts. Periodic Acid-Schiff staining demonstrated increasing glycogen and glycoprotein deposition in the epidermis and hair buds while trichrome staining revealed areas of dense connective tissue deposit within hair bulbs and shafts, as well as in the dermis, particularly in the head and dorsal regions. These findings provided crucial insights into the ontogeny of skin development in RSG, revealing key changes that might be essential for thermoregulatory adaptation in RSG.