A large osteosarcoma in the mandible of an ox

A three years old ox was referred to the University of Zambia Veterinary Clinic with a large protruded mass in the mouth. The slow growing oral mass was noticed three months earlier and contained displaced, loosely embedded incisor teeth. On clinical examination the mass was firm, large, round and located anterio-dorsally in the mandible. Histo-pathologically, tumor mass composed of neoplastic osteoblasts exhibiting osteoid and immature trabecular bony production. Neoplastic cells were positive for osterix marker expression. Gross pathology, radiology, cytology, immunohistochemistry and histopathology confirmed the mass as a mandibular osteosarcoma. This is a first and rare case of mandibular osteosarcoma being reported in cattle from Zambia and should be included in differential diagnosis of oral mass in cattle.