RESUMO
This paper describes a case of malignant melanoma in brown coat horse, which had ataxia and proprioceptive deficits in hind limbs, progressing to permanent decubitus. The animal was euthanized and the final diagnosis was based on necropsy and histopathology. At necropsy different masses and / or nodules in skeletal muscle, bone, abdominal cavity, lungs, heart, spleen, liver, adrenal gland, lymph nodes, brain and cerebellum were found. Neurological clinical signs presented by the animal were justified by spinal cord compression caused by melanocytic mass invading the medullary canal of the flow segment of the thoracic spine (between 15th and 18th thoracic vertebrae). This is the first case report of melanoma leading to spinal cord compression in a non-gray horse. Thus, it is important to include this neoplasm in the differential diagnosis list of cutaneous and subcutaneous masses and / or nodules, and in suspected cases of spinal cord compression in horses of any coat.(AU)