Surgical Correction of Third Degree Rectogaginal Fistula (RVF) in a Mare

Abstract

Rectovaginal fistulas (RVF) occur during foaling or secondarily to dystocia. The injury occurs mainly in primiparous mares. There are many reasons to why it occurs. Strong expulsive forces by the mare, along with malposition of the fetus, during parturition, like foot-nape posture or dorsopubic position can cause RVF. During the process of foaling, a mare who had never given birth before experienced severe rectovaginal lacerations classified as third degree. This unfortunate incident occurred when the fetus's hoof became trapped in the birth canal. In an attempt to extract the fetus, the owner exerted force without properly adjusting the mare's posture, position, and presentation, resulting in significant tears in the vagina and rectum. Upon examination, it was discovered that a fistula had formed, connecting the rectum and vagina. The mare underwent surgery and received postoperative care which included the administration of antibiotics (specifically, 10g of Ceftriaxone in normal saline via intravenous injection daily for 7 days) and analgesics (1ml of Ketoject per 40kg of body weight via intravenous injection for 3 days). The mare had access to water at all times and was given a small amount of lush green fodder twice a day. Laxatives were added to the feed to maintain regular fecal consistency and prevent the formation of hard fecal masses. During the first week, the mare was confined to a specific area, and in the second week, an assistant provided hand walks for exercise. The skin sutures were removed after a few weeks, and the mare was continuously monitored until it made a full recovery.