A 3-year-old female dog was referred to the clinics of İstanbul University with the complaint of abdominal distention. On the basis of the clinical findings and ultrasonography, a mass was detected in the left ovary. An ovariohysterectomy was performed. Grossly, the mass, with dimensions of 15 × 11 × 8 cm, weighed 1.2 kg and contained hairs, cysts, fat, bone, and cartilage on the cut surface. Histology revealed the occurrence of well-differentiated components of all 3 germ layers and the mass was diagnosed as a benign mature cystic teratoma.

A 3-year-old female dog was referred to the clinics of İstanbul University with the complaint of abdominal distention. On the basis of the clinical findings and ultrasonography, a mass was detected in the left ovary. An ovariohysterectomy was performed. Grossly, the mass, with dimensions of 15 × 11 × 8 cm, weighed 1.2 kg and contained hairs, cysts, fat, bone, and cartilage on the cut surface. Histology revealed the occurrence of well-differentiated components of all 3 germ layers and the mass was diagnosed as a benign mature cystic teratoma.