Cryopreserved equine amniotic membrane and its use in cutaneous wounds of horses

This study aimed to evaluate the use of equine amniotic membrane (EAM), frozen indirectly using liquid nitrogen and stored between −10° and −24°C, in the treatment of equine skin lesions. Six healthy female horses, aged 3-10 years, were included in this study. EAM was collected from previously evaluated healthy parturient mares. Wounds were surgically created at the distal ends of the forelimbs. One limb was chosen for treatment, and the contralateral limb was chosen as the control. Pain sensitivity, presence of granulation tissue, secretions, and bleeding after debridement during cleaning were evaluated. Microscopically, the following were evaluated: the integrity of the epithelium, the organization of the connective tissue, the presence of hemorrhage, fibroplasia, epithelial hyperplasia, hyperkeratosis, neovascularization, and the types of cells present. Assessments were performed on days 0, 3, 7, 14, 21, 28, and 63, and the time to complete the lesion closure. Treatment with EAM promoted faster recovery, greater neovascularization, better quality fibroplasia, and less sensitivity to pain than the control group. We concluded that the use of EAM was advantageous compared to the control group.