Ovarian Cysts in the Bitch: An Update

Functional ovarian cysts occur as solitary or multiple fluid-filled structures of variable size that are unilateral or bilateral in the bitches of age 6-8 years. Though the pathogenesis is obscure, insufficient LH surge, intrafollicular changes in gonadotrophin receptors and growth factors are the possible reasons behind the occurrence of hormonally active ovarian cysts that predisposes the bitch to the development of cystic endometrial hyperplasia-pyometra complex and occasionally hyper estrogenism. In the presence of suggestive signs, ultrasonography is the practical imaging modality for the clinical diagnosis that can be confirmed by assay of ovarian steroids and histopathology. Medical management with gonadotrophin-releasing hormone analogues and human chorionic gonadotrophin is not preferred as they are not always successful. As uterine pathologies are highly likely by the time of diagnosis, ovariohysterectomy is the treatment of choice for the follicular and luteal cysts. Understanding the cellular and molecular changes in the hypothalamo-hypophyseal ovarian axis will improve our understanding on the canine ovarian cysts.