Laparoscopic evaluation of oviductal patency in the standing mare.

Intraluminal masses in the oviduct might cause infertility and/or subfertility in mares by preventing transport of ova, sperm, or both, to the site of fertilization or the embryo into the uterus. Currently, there is no clinical test for oviductal patency in mares. The objective was to determine if the passage of microspheres from the oviduct to the uterus was associated with the presence or absence of intraluminal masses. In this trial, a standing laparoscopic technique was used to cannulate the oviducts and instill 15-μm fluorescent beads in 16 light-breed mares. At 48 hours after surgery, uterine lavage was performed to collect and quantify the number of beads transported to the uterus. Mares were immediately euthanized, and their reproductive tracts recovered. The presence of intraluminal masses was determined from postmortem evaluation and compared with the number beads recovered in the uterine lavage fluid. A test was considered positive for intraluminal masses if no beads were transported to the uterus. The sensitivity and specificity of the test were 71.4% and 85.7%, respectively.