Histomorphological differentiation of the skin of leopard (Panthera pardus), leopard cat (Prionailurus bengalensis), Bengal tiger (Panthera tigris), and golden jackal (Canis aureus)

Background and Aim: Leopard (Panthera pardus), leopard cat (Prionailurus bengalensis) Bengal tiger (Panthera tigris), and golden jackal (Canis aureus) are carnivores. Leopard and Bengal tiger are listed in the red list as vulnerable species by the International Union for Conservation of Nature and Natural resources. Leopard cat and golden jackal are grouped under animals of least concern. A wide variation exists in the structure of the skin and pattern of hair follicles among domestic and wild mammals. Thus, the study aims to create a baseline data on the skin of leopard, leopard cat, Bengal tiger, and golden jackal and the data so obtained may form an indispensable tool in wildlife forensics. Materials and Methods: Skin samples of leopard (n=3), leopard cat (n=4), Bengal tiger (n=3), and golden jackal (n=4) were collected from the Department of Pathology, College of Veterinary and Animal Sciences, Pookode. The samples were processed for paraffin embedding. Horizontal and vertical sections of 5 μm thickness were used for histological staining techniques. Observations on the layers and features of epidermis, hair follicle pattern and glands, namely, sweat and sebaceous were recorded. Results: Skin comprised an outer epidermis and an inner dermis. Keratinized stratified squamous epithelium made up the epidermis. Stratum basale, stratum spinosum, stratum granulosum, and stratum corneum were discernible in leopard, Bengal tiger, and golden jackal. In leopard cat, stratum basale, stratum spinosum, and stratum corneum were present. Compound hair follicles were a characteristic feature of all species. However, the pattern varied. In leopard, leopard cat and Bengal tiger, a single large primary guard hair was encircled by compound follicles. The number of surrounding compound follicles ranged between five to seven in leopard, two to five in leopard cat, and three to seven in Bengal tiger. Each compound follicle, in turn contained, one to two coarse primary hair follicles and several fine secondary hair follicles. Compound follicles arranged as clusters of three were a salient attribute in jackal. The central follicle was comparatively larger than the lateral ones. Each compound follicle comprised a single long, primary hair, and six to eight smaller secondary hairs. Conclusion: Histological variation in the skin of the leopard, leopard cat, Bengal tiger, and golden jackal was established. The data form a valuable basis for comparative histology of wild carnivores. Further, the data may be of value in the identification of the unknown skin samples of wild carnivores