Characterization Of Normal Skin Thickness For Various Body Regions, Ages, And Genders Of Yucatan Miniature Swine

By Brown L., Kim D.Y., Hanks C., Brocksmith D., Hodges M., Liu J., and Bouchard G.F.

Dermatology is a vital field, as the skin plays a crucial, life-sustaining role in protecting both humans and animals. As the largest organ of the body, the skin is metabolically active, constantly shedding and regenerating. Skin across different regions of the body may vary in morphology, including physical thickness. Dermatological studies in miniature swine provide a unique opportunity for risk assessment due to their demonstrated similarities to human cutaneous anatomy, biochemistry, and physiology.

The Yucatan miniature swine, a commonly used breed in biomedical research, is known for its slate grey-black skin, which is slightly or moderately pigmented and sparsely covered with hair (sometimes referred to as the Mexican hairless miniature swine). The physical thickness of miniature swine skin may influence drug absorption in in vivo or ex vivo studies, as well as affect wound healing or phototoxicity studies. Therefore, understanding the relative dimensions of each major skin application or collection site is essential. This study on Yucatan skin aims to better document skin thickness to provide researchers with more comprehensive information on miniature swine skin.

While there are few citations on the thickness of porcine or miniature swine skin, previous studies, such as Eggleston et al. (2000), reported the mean epidermal thickness of the Yucatan miniature swine's flank and dorsal neck to be 68±34 µm and 68±25 µm, respectively. These values closely resemble the thickness of human facial (68±26 µm), neck (65±24 µm), and arm (68±21 µm) epidermis. In contrast, the domestic Yorkshire swine epidermis was thinner. Other studies, like those by Monteiro-Riviere et al. (1990), reported backskin components in domestic Yorkshire swine, including a 12.28±0.72 µm stratum corneum and a 51.89±1.49 µm cellular epidermis. This study will contribute additional standard data on Yucatan miniature swine skin thickness to the broader research database.