Abstract
Ovarian teratomas are rare neoplasms in female dogs, and they are characterised by the proliferation of tissues of embryonic origin. Most teratomas are benign, but a histological diagnosis is important for clinicians. The objective of this article is to describe a benign ovarian teratoma in a dog, which was found on the street and was appearing like pregnant. A veterinary inspection by palpation documented an enlarged abdomen with a mass of tough matter located on the right side in the abdominal-pelvic part. An ultrasound examination presumed neoplastic mass in region of ovary. A bilateral ovariohysterectomy was performed and the subsequent histological evaluation revealed a benign ovarian teratoma with a histochemically and immunohistochemically verified nervous tissue. After one year, no distant metastases were found and the dog was recognised as being clinically healthy without problems. On the basis of the ultrasonography diagnostics and histopathological analyses, we have demonstrated the occurrence of a benign ovarian teratoma in a dog.