A case of melanosarcoma-in rat

A nine month old male rat died in the Institute of Pharmacedutical Science, GGV, Bilaspur (C.G.). The owner observed the grayish spot on skin, after 10 days of first observation the affected area became hard as like corn and rat died suddenly within 45 days. Before death rat showed abdominal pain, blood tinged urine, weakness, dullness and loss of body weight. The carcass revealed dome shaped sessile blackish, grayish nodule about 0.8 centimeters in diameter on the right renal parenchyma. Microscopically, small spindle shape cell, polyhedral epithelioid shape cells with eosinophilic cytoplasm were observed in affected rat.