Differences in thickness of dermal layers in cranio-caudal anatomic locations in porcine skin wounds: Implications for wound healing studies

The use of the domesticated swine is important for advancing our understanding of healing in human skin due to the architectural similarities in their skin. In swine wound studies, skin thickness may play a role in healing due to the anatomical variation in the thickness of the different skin compartments, such as the dermis and subcutaneous fat, as well as the differences in anatomical location of the wounds. Here, the thickness of different skin compartments were measured in excisional wounds created in different anatomical locations along the cranio-caudal axis. Full-thickness, 2 cm diameter circular excisions were created on the dorsal paravertebral area of pigs. Thickness of the dermal and adipose layers of excised tissues at day 3 post-excision were measured in fixed H&E sections. Wound re-epithelialization was measured on excised day 10 wounds. A significant difference in skin thickness between the cranial wounds compared to the caudal wounds is noted in skin excised down to the landmark of the subcutaneous fascial plane. There were also significant differences in the thickness of the dermal and fat layers. Skin thickness, and the variations of the dermal and fat compartments, and locations of wounds should be taken into consideration in porcine wound studies as they may contribute to alterations in healing in the different locations.