Two bitches showed urinary incontinence shortly after having been ovariohys
terectomized. With abdominal ultrasound an anatomical defect of the right u
reter was suspected in one case. Intravenous urography showed a hydroureter
terminating in the direction of the uterine stump and retrograde vaginogra
phy was diagnostic in both cases for a uretrovaginal fistula. An adhesion b
etween ureter and vagina was dissected during exploratory laparatomy and th
e ureter was re-implanted into the bladder. Both bitches are free of clinic
al signs thereafter. Uretrovaginal fistulas can be a complication of a rout
ine ovariohysterectomy if one of the ureters is inadvertently enclosed into
the ligature.