COMPARATIVE TOPOGRAPHICAL AND HISTOMORPHOMETRICAL STUDY OF THE HAIR, HAIR FOLLICALE AND HAIR DENSITY IN THE SKIN OF LOCAL BLACK MALES GOAT

The study aimed to undergo a comprehensive study to provide abroad basic data for thedifferent constituents of the skin of local black goat. To achieve this goal, histological,morphometrical and topographical study was carried out on twelve skin regions taken from twentymale apparently healthy bucks. All samples were collected during the autumn season.Two types ofhair follicles were noticed: large follicles that extend deeply into the dermis; Which representedprimary hair follicles, smaller and shorter but more numerous; called secondary hair follicles. Theprimary hair follicles produce the coarse hair while the secondary hair follicles produce the finehairs. The diameter of the coarse hairs varied in the different skin regions and ranged between(39.98-106.40  m) being larger in the back and lateral surfaces and smaller in the abdomen andmedial surfaces. The diameter of fine hairs ranged between (26.56-39.94  m). The secondary:primary hair follicle ratio varies in the different skin regions and accordingly the fine :coarse hairratio varies as well. The fine: coarse hair ratio was found to be 6.88:1 in the middle back region,5.89:1 in the lateral surface of forelimbs region, 5.86:1 in anterior back region, 5.46:1 in lateralsurface of hind limb, 3.64:1in medial surface of hind limb, 3.32:1 in the skin of theabdomen,3.25:1 in the medial surface of the forelimb, 2.82:1 in the skin of the tail, 2.10:1 in theskin of scrotum, 0.20:1 in the skin of the muzzle, 0.15:1 in the dorsal surface of skin of the ear and0.00:1 in the ventral surface of the skin of the ear. Most of the hair follicles of different regionswere of a compound type in which several secondary hairs share the opening of a primary hairfollicle. In less common circumstances, the secondary follicles open directly on the epidermis butthey remain in a close position to the opening of the accompanied primary follicle. Simple hairfollicles were observed in the ventral surface of the skin of the ear, and in a less extent in thescrotal regions, muzzle region and skin of the dorsal surface of the ear. Hair density varies greatlyin the different skin regions being: 31.68/mm2 in anterior back region, 32.66/mm2 in the middleback region,13.38/mm2 in the abdominal region, 32.76/mm2 in the tail region, 30.30/mm2 in thelateral side of forelimb, 12.50/mm2 in the medial side of the forelimb, 11.52/mm2 in the scrotalregion, 31.12/mm2 in the lateral side of hind limbs, 16.44/mm2 in the medial side of hind limbs,22.22/mm2 in the muzzle region, 9.62/mm2 in the skin of the dorsal surface of the ear and2.92/mm2 in the skin of the ventral surface of the ear.