Mare vagina. Why Mares Squirt When in Heat: The Biology Behind It Mares may squirt fluid from their vagina when they are in heat. Changes in the anatomy or interruption in the function of any section can contribute to reproductive problems. Even though it may not be the most fun part of owning a horse, you will occasionally need to clean your mare's udders and genital area. The vagina is the muscular tube that extends from the cervix to the outside of the mare’s body. The vulva is 2-3 in. This is a cranioventral recess in the mare. Prior to insertion the split dorsal blades and wider ventral blade are rotated a quarter of a turn. The cervix projects into the vagina at its anterior aspect. . However, vulvar winking also occurs when the urinary tract or vulva is irritated. ffzwt p3o bcae4 ad4yx prv 9vkea i6sk pvjq 19v efoz