Female pseudohermaphroditism in a Dorset sheep: a case report

Abstract

A four-month old Dorset lamb was presented to the University of California-Davis (UCD) Veterinary Medical Teaching Hospital (VMTH) for correction of an inguinal hernia and castration. On physical examination, testicles were not found in the scrotum and it was presumed to be a cryptorchid ram with an inguinal hernia. Surgical exploration of the abdomen identified an intact uterus, cervix, vagina and bilateral ovaries. The urethra exited the bladder via a functional fibroelastic penis. The lamb was slaughtered at 11 months of age and the reproductive tract was harvested. The lamb had a 54-XX genotype and the gonads were histopathologically confirmed to be ovaries. A fully intact female internal reproductive tract, in conjunction with functional male external genitalia, identified this lamb as a female pseudohermaphrodite. In livestock, freemartinism and male pseudohermaphrodites are more commonly reported, whereas female pseudohermaphroditism is rare. In this case report we describe the first documented case of female pseudohermaphroditism in sheep.