Regional skin histomorphology in adult greater cane rats (Thryonomys swinderianus): A pilot study

Abstract

The greater cane rat (Thryonomys swinderianus) demonstrated numerous dermal architectural peculiarities hitherto unreported. This investigation assessed and evaluated certain histologic features of skin samples from the fore and hind limbs, the neck, head, proximal to the ear and oro-nasal regions for follicular evaluations and micro anatomic assessments in the adult species. Twenty wild taken animals of equal gender distribution were used for histologic assessments of structural elements and histo-morphometric evaluations. Hair follicular density, size, distribution and orientations as well as sexual dimorphisms observed in the body regions studied with Motic Image Plus software analysis were also reported. Statistical analysis revealed sexual dimorphism in this feature as females demonstrated significantly higher (P < .05) follicular density and epidermal thickness at about twice the recorded values for males at similar sites evaluated, but half (P < .05) of follicular diameter of values of males. Mean follicular density for oro-nasal area, head, neck, fore and hind limbs were 50 ± 3.55 and 70 ± 3.34n/µm², 16.24 ± 3.02 and 12 ± 4.00, 8.00 ± 2.68 and 83.66 ± 4.08, 8.02 ± 4.00 and 3.23 ± 3.85, 4.32 ± 3.02 and 2.05 ± 2.04 for females and males respectively. Follicular area decreased proportionally with density increase but it was inversely proportional with epidermal thickness in all evaluated regions. This investigation suggests that the peculiarities observed in dermal structures adapt this species to environmental forces, defense and self-preservation including thermoregulation, foraging and predator evasion, whereas histo-morphometric evaluation result suggests that thermoregulation and other skin sensory modalities may differ between genders in the greater cane rat.