Vaginal hyperplasia in an adult female mouse ( <i>Mus musculus</i> ) responsive to ovariohysterectomy

Abstract A 7‐month‐old, female, pet, domestic mouse was presented for a referral with a short history of a possible pelvic organ prolapse. The mouse was systemically well and had received antibiotic and anti‐inflammatory therapy from the primary care clinician. No improvement was seen. The animal belonged to a colony of three female mice and had never been bred from. On presentation, hyperplastic tissue was protruding from the vulva, but did not interfere with urination and appeared healthy on examination. Conscious reduction was not possible. As the animal was largely asymptomatic, the initial treatment included continued anti‐inflammatories and monitoring with no further response. Subsequently, an ovariohysterectomy was scheduled during which the uterine horns were observed to be subjectively enlarged; histopathology was declined. The patient recovered uneventfully, and vaginal hyperplasia was fully resolved within 10 days post neutering.