Congenital melanoma in a heifer

The clinical, intra-operative and pathological findings taken from a case of melanoma in a 9-month-old female Holstein Friesian heifer are reported here. The tumor, hanging on the right side of the thorax, was present at birth and increased in size with time. Muscular invasion by tumoral tissue was detected during surgery. Histological and cytological data indicated that the neoplasia (melanocytoma) was benign but the prognosis, related to the invasiveness of this neoplasm, was considered reserved. Melanoma is a rare tumor in cattle, often congenital, although already reported in pigs and in horses.