Two Different Neoplasms in Cougar (Puma concolor): Pheocromocytoma and Ovarian Fibroma - Abstract
The cougar (Puma concolor) is the second largest felid species in the Americas and the fourth largest in the world. In literature, there is abundant data on domestic animals’ neoplasms; however information on neoplasms occurring in wild animals is limited. This study was carried out on a 33 kg female, adult cougar specimen kept for approximately 16 years at Sorocaba Zoo. Hyporexia, progressive weight loss and increased abdominal volume were reported by the animal’s handler. At necropsy, ascites with serosanquinolent content, pyometra, peri-mammary lipoma and presence of a mass in the left adrenal region and in the left ovary region were observed. The adrenal formation was 7 x 7 cm, dense and vinaceous in color. Samples of all organs and masses were collected and stored in 10% formalin and, afterwards, processed by the routine technique for histopathological evaluation. The immunohistochemical examination of the adrenal mass showed an infiltrative growth of neuroendocrine origin, positive for Cromagranin and Synaptophysin and negative for AE1 and AE3 (cytokeratin), compatible with pheochromocytoma. The zoos prolong the life expectancy of their animals, when compared to that of wildlife individuals, resulting in higher incidence rates of neoplasms. Preventive veterinary examinations of wild animal collections remain a good strategy for conserving biodiversity. Further studies should be carried out to enable diagnosis in early stages, thus allowing a favorable prognosis for affected animals, with the possibility of therapeutic or surgical interventions. Data about neoplasms occurring in wild animals ex situ, might help in the conservation of species in situ.