Where would epitheliogenesis imperfecta typically be found on a horse?

Epitheliogenesis imperfecta is a congenital condition characterized by the absence of parts of the skin or mucous membranes, leading to areas where the epithelium (the outer layer of skin) does not form properly. In horses, this condition most commonly affects the skin, as it is primarily related to issues in the development of epithelial tissues. The absence of skin can often result in patches that are exposed and vulnerable to infection, and this condition is notably identified in foals.

While the other options may have their own types of abnormalities or conditions, they do not directly relate to epitheliogenesis imperfecta. The eyes may experience various disorders, the hooves can develop different pathologies, and the mane might face issues like hair loss, but none of these are typically associated with epitheliogenesis imperfecta in the same way that the skin is. Therefore, skin is the correct context for this condition in horses.