Comparative Photomicrographic Examination of Integument From Eight Species of Mammals Including Two Lineages of Research Miniswine
Introduction: Skin is the largest organ in the body. Animals have skin which is generally similar to human skin, however, species specific anatomical and biochemical differences exist. The integument of animal models may vary in skin surface topography, overall thickness and thickness of specific layers, stratum corneum, epidermis, dermis density and collagen content, regional blood flow, pelage (hair count), hair follicle size or density, and sub-dermal characteristics. Determination of which animal model most closely matches the skin of humans is important for translational dermal research.
Objective/Rationale: Prepare magnified images of comparative skin histology and perform simple image analysis for differences or similarities.
Methods: Animal skin samples collected included Yucatan miniswine, Hanford miniswine, Cynomolgus monkey, Beagle dog, NZW rabbit, Hartley guinea pig, Sprague-Dawley rat, and CD-1 mouse. The human skin was acquired from a medical school. Samples were fixed in neutral buffered formalin, processed, sectioned, stained with H&E, examined by microscope and photographed by veterinary dermatopathologist (DYK). The resulting skin images generated by Olympus MicroSuiteTM were compared side-by-side at equivalent magnification.
Results: Visual comparison of images suggest the skin of swine and human look the most similar while the skin of rodents (rat, mouse) has a much thinner epidermis. The skin of rabbit and guinea pig appear to consist predominantly of hair shafts/hair follicles combined with thin epidermis. Monkey and dog skin were next most similar to the human skin.
Conclusion(s): The swine (Yucatan & Hanford) skin images are visually most like those of the human images.
Brown, L., Kim, D.Y., Hanks, C., Schnapp, S., Brocksmith, D., White, D., Stricker-Krongrad, A., Liu, J., Bouchard, G.F.