Sex-related variations in the morphological structure of puma (Puma concolor Linnaeus, 1771) ear skin

The ear tissue of vulnerable felines, such as the puma, holds potential biological material for creating biobanks. However, skin composition can differ significantly between individuals of the of the same species and even between sexes, based on different environments. Therefore, identifying morphological similarities across these populations is crucial for developing accurate protocols. This study aimed to characterize and evaluate the structure and composition of ear skin in both a male and a female puma using histological techniques. Histomorphometric analysis revealed a total thickness of 304.65 µm and 238.95 µm for the male and the female, respectively. The epidermis was notably thinner in the female compared to the male. Specifically, the thickness of the basal, spinous, and corneum layers in the female was 2.62 µm, 10.07 µm, and 3.15 µm, respectively, compared to 3.49 µm, 13.94 µm, and 3.66 µm in the male, respectively. Melanocytes, keratinocytes, and fibroblasts totaled 26, 24, and 50 cells in the male and 21, 25, and 54 cells in the female. Moreover, chondrocytes (male: n=33 and female: n=41) and perichondrium (male=13.99 µm and female=9.05 µm) were observed in the cartilage. These results demonstrate the histomorphometric differences and similarities between a male and a female puma, consistent with observation in other felines. This information is relevant for a targeted approach for establishing biobanks for this species.