Faculty of Veterinary Medicine, Urmia University Veterinary Research Forum 2008-8140 Articles in Press 2026 08 08 Characterization and Distribution of Interstitial Cells of Cajal in Healthy Stomachs of Equids: A Comparative Study between Species (Horses, Donkeys and Mules) 738625 10.30466/vrf.2025.2060653.4760 EN Angie Lorena Medina Bolivar UNIVERSIDAD DE ANTIOQUIA 0009-0004-0549-2208 Julian David Muñoz Duque UNIVERSIDAD DE ANTIOQUIA 0000-0003-2492-2889 Jose Ramon Martinez Aranzales Equine Medicine and Surgery Research Line (LIMCE), CENTAURO Research Group, School of Veterinary Medicine, Faculty of Agricultural Sciences, Universidad de Antioquia, Medellin 050010, Colombia 0000-0003-2428-1372 Journal Article 2025 05 14 Interstitial cells of Cajal (ICC) play a crucial role in regulating gastrointestinal motility, functioning as pacemakers in the digestive system of equids. This study described and compared the ICC populations in different regions of the stomachs of equids (horses, donkeys and mules). A total of 30 healthy stomachs from horses, donkeys, and mules were evaluated using immunohistochemistry and high-resolution microscopy to assess various regions of the stomach in these species. The results showed the presence of ICC in all three equid species, with a predominance in the submucosa across the squamous mucosa, glandular mucosa and pyloric antrum. The density and morphology of ICC varied slightly between species, although no significant differences were found. Among the equids studied, donkeys showed the lowest ICC density, while horses exhibited the highest in the evaluated tissues. Four cellular morphologies were identified, three of which were included in the analysis, as toluidine staining revealed that one corresponded to mast cells. Further studies are needed to elucidate dynamics and possible alterations in response to gastric pathologies.