Eversion of the bovine bladder

Case Report

Abstract

Most often, prolapse of the bladder (prolapsus vesicae) is observed by rupture of the wall of the vagina in connection with difficult parturition. Due to a short and wide urethra, eversion of the bladder is especially common in the mare, and almost solely related to parturition, characterised by strong contractions. In spite of a longer and more narrow urethra, eversion of the bladder does occur in cows from time to time, but these cases are also solely related to parturition. This fact is obviously caused by contractions related to birth, but also by walls of the urethra relaxing in this period. Paresis of the bladder may also result in a case of eversion.

When everting, the bladder turns inside out and is forced out through the urethra - to be found in the vagina or outside labiae in the form of a prolapse the size of a child's head. Soon after the eversion, changes in the mucosa of the bladder occur, as it turns bluish, thickens, and feels oedematous. At this stage, it is not immediately obvious that the prolapsed part is the bladder, and the diagnosis must be established at a thorough examination. The base of the prolapse, in a case of an everted bladder, can be found in the entrance of or inside the urethra.

From a point of differential diagnosis, the following must be considered: Prolapsed bladder without inversion, vaginal polyps, vaginal prolapse, vaginal tumours, and the fetal membrane bladder.