Rachel Pereira da Rocha Miranda, B Miranda, Andressa Borges Aranha, Maria Fernanda Bruno Gomes Ramos, Edson Pereira de Oliveira, Bruno Stéfano Lima Dallago, José Adorno, Isabel Luana de Macêdo, Márcio Botelho de Castro, Rita De Cássia Campebell
Background Skin wounds are common in horses due to species-specific behavioral responses. Equine skin morphology, vascularization, and inflammatory responses to wounds are comparable to those in humans, supporting the translational relevance of equine wound-healing studies. Investigating biomaterials such as tilapia and frog skin may improve wound management. This study demonstrated that sterilized tilapia and frog skin exhibit promising wound-healing properties. Materials and Methods Macroscopic, microscopic, and thermographic aspects of second-intention wound healing were compared in six horses with surgically induced skin wounds treated topically with frozen tilapia skin (FTS), sterilized tilapia skin (STS), sterilized frog skin (SFS), or lactated Ringer’s solution (CW). Wounds were created bilaterally in the thoracolumbar region, with one side designated for histopathological evaluation and the contralateral side for macroscopic assessment, including photographic documentation, wound area measurement, contraction rate, and thermographic analysis. Treatments were applied daily, and wound progression was monitored for 28 days. Evaluations were performed on days 0, 3, 7, 14, 21, and 28 after wound induction. Results No clinical abnormalities were observed in the horses throughout the study. Regarding wound area, the FTS group exhibited the largest lesions on day 14 compared with the CW group. Over time, the CW and FTS groups showed reduced wound contraction, with increased wound area on day 7. Histopathological evaluation revealed a significant increase in polymorphonuclear cells (PMNs) in all groups on day 3, which persisted until day 7 in the CW group and until day 28 in the FTS group. Thermographic analysis showed no significant differences among treatments. Conclusion Sterilized tilapia skin reduced the inflammatory response, enhanced wound-edge contraction, and accelerated healing. Frog skin was associated with faster reduction of edema and hemorrhage, as well as more pronounced fibroplasia during the early stages of healing. In contrast, frozen tilapia skin showed limitations, including lower adherence to the wound bed, increased contamination, and delayed healing.