Equine melanotic disease: description and histopathological case study.

摘要

A clinical case of a 12 year-old dapple-gray horse affected by a paresia of the hind quarters, of a probable neural origin that failed to respond favourably to conventional treatment is described. Having reached a persistent sternal decubitus, the horse was sacrificed and postmortem examinations made. The existence of variable sized round to oval shaped nodules was verified (from some mm up to 12 cm), in a great number of organs (sacrum spinal cord, spleen, adrenal gland, striated muscles, myocardium and others). Histopathological studies confirmed that the nodular formations were formed by fibrous conjunctive tissue, containing in their interior melanocyte cells and melanoblasts. From the results of the immunohistochemical studies, the existence of melanocytes was confirmed and from their reduced proliferation rate it was concluded that they were benign melanotic tumours.