Vol. 9, Special Issue 1 (2024)

Author(s): Raghu Naik K, Indu VR, Maya S, Rajani CV, Patki HS and Surjith KP

Abstract: Ultrastructural studies were conducted on the skin of Vechur cattle of Kerala. Skin samples of 1 cm² size were collected from 15 different regions viz., dorsal, ventral and lateral regions of head, neck, abdomen and tail respectively and muzzle, interdigital region of fore and hind limbs. For Scanning Electron Microscopy (SEM) samples of skin were fixed in 2.5 percent gluteraldehyde in 0.1M phosphate buffer (PBS) (pH 7.2) for 12 h at room temperature and post fixed in one percent aqueous osmium tetroxide for two hours at 4 ºC followed by 1X PBS washing twice for 30 min each as described by Shapiro et al. (2019) in rabbits. After standard procedures, the samples were subjected to electron beams for Visualization under monitor at accelerating voltage of 20kV. In scanning electron microscopy, a set of rectangular-shaped deep channels were observed on the epidermal surface. In the muzzle area, hexagonal-shaped raised regions were separated by narrow, deep grooves. Oval-shaped openings of the nasolabial glands were visible on the muzzle's surface, with irregular borders caused by numerous sulci. Within the stratum corneum, there were four to five layers of well-defined, scale-like flattened keratinised dead cells. Dermal papillae were seen as upward protrusions in the papillary dermis. A significant number of collagen fibres ran parallel to the skin's surface, with some exhibiting a longitudinal and concentric arrangement around the sweat glands, sebaceous glands, and hair follicles. Elastic fibres formed a sponge-like elastic system in the papillary dermis. The collagen fibre bundles in the reticular dermis were thicker in comparison to those in the papillary dermis. The hair follicles in dermis were confined to the upper third or fourth of the thick dermis. Numerous delicate elastic fibres formed a network and enveloped the hair bulbs located in the lower part of the follicles. Pairs of lobulated sebaceous glands were observed in the reticular layer of the dermis.