Texas Equine Veterinary Association

www.texasequineva.com • 7 until the fluid is relatively clear. Alternatively, some veterinarians like to infuse a dilute (< 2% final concentration) povidone-iodine solution diluted in either water or isotonic saline. Oxytocin can be given during the final siphoning to facilitate removal of excess fluid from the uterus. Manual Removal of Retained Fetal Membranes Manual removal of fetal membranes was the first reported method for the treatment of retained fetal membranes (Vandeplassche et al., 1971) and still remains a highly utilized method by many veterinarians in Australia and the U.S. (Warnakulasooriya et al., 2018). Several different methodologies for manual removal of fetal membranes has been describes over the years. The simplest is grasping the portion of the placenta outside the mare and providing traction. Some practitioners advocate separating the endometrium from the chorioallantois by placing a hand or wooden ring between the two tissues to aid separation. Others will twist the chorioallantois in one direction until the tissue is tight, like a rope, to provide traction (Threlfall, 2011). Another method described uses a scissor action by the fingers to separate the endometrium from the chorioallantois until a uterine horn is reached and then wrapping the hand and fingers around the chorioallantois in a ring like fashion. The hand is then moved up and down the placenta to separate the fetal membranes from the uterus (Burden et al., 2018). When using manual removal of fetal membranes, gentle traction can be used; however, forcible removal can result in endometrial trauma, hemorrhage, invagination of the uterus, delayed cervical closure, and tearing the placenta thus leaving placental remnants in the uterus (Knottenbelt et al., 2003; Threlfall, 2011). For these reasons manual removal has been discouraged by some. Recent research has renewed interest in examining manua l removal of retained fetal membranes as a treatment. Sevinga et al. (2002) compared the post-partum reproductive performance of Fresian mares with retained fetal membranes to those without retained fetal membranes and found no difference in foal heat pregnancy rate, subsequent cycle pregnancy rate, or pregnancy loss. Additionally, they compared Fresian mares treated for retained fetal membranes using manual removal compared to oxytocin treatment and found no differences in pregnancy rates or pregnancy loss (Sevinga et al., 2002). Cuervo-Arango et al. (2009) compared fertility after manual removal of fetal membranes immediately post-foaling to those which passed spontaneously. They found no difference in any of the fertility parameters examined. These two studies suggest, when done carefully and properly, manual removal of retained fetal membranes is a valid option for the equine practitioner. "Dutch" Technique In 2015, Meijer et al. published a paper looking at infusion of water in an umbilical vessel for the removal of retained fetal membranes. They found in 92% of cases the fetal membranes were passed in 5 to 10 minutes. This has since garnered interest by veterinary practitioners due to the simplicity of the procedure and rapid results. Equipment needed for the procedure are a scalpel blade, small diameter tube (i.e. stallion catheter, Harris flush tube or foal nasogastric tube) and a water hose attachment with water flow regulation valve. The water hose attachment with water flow regulation valve can be constructed from material obtained from a hardware store using a restricted-flow water shut off valve and a threaded hose barb adaptor (Fig. 1). A stainless steel adjustable Figure 1. A) Photograph of the water flow regulation valve constructed using a restricted-flow water shut off, a threaded hose barb adapter and stainless steel adjustable with a Harris flush tube attached used with the "Dutch" technique. B) Close up photograph of the water flow regulation system.

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