Ovarian Teratocarcinoma in an Emu (Dromaius novaehollandiae): Histopathological and Immunohistochemical Characterization.

A 17-year-old female emu (Dromaius novaehollandiae) was presented for clinical evaluation due to a 3-week history of anorexia and progressive weight loss. The emu died after sedation. At necropsy examination, the ovary and the majority of the oviduct were effaced by a multinodular cystic mass and accompanied by 6 l of coelomic effusion. Histopathology revealed a neoplasm composed of well-differentiated, poorly organized tissues derived from ectoderm, mesoderm and endoderm. Tissues within the neoplasm expressed glial fibrillary acidic protein, desmin and cytokeratins AE1/AE3, respectively, confirming the diagnosis of teratocarcinoma.