Mare Anal A mare’s external genitalia (vulva) plays an integral part in her ability to function as a broodmare, particularly during early breeding stages. For optimal performance as a broodmare, the conformation of her vulva should remain vertical rather than slanting toward either anus or downward; otherwise it risks contamination of vestibule and vagina with fecal material that could lead to infection of her uterus.
As part of a reproductive examination, one must inspect both the ovary and uterus. Ovulation in mares occurs at an indentation on their ovaries known as an “ovulation fossa,” which can be easily identified using palpation with fingers and thumb. A large fossa often signals impending ovulation; its best location can be detected using palpation with index finger and thumb (Figure 2).
Once the perineum/vulva of a mare has been meticulously cleaned, disinfected, rinsed and wrapped, a gloved hand can be introduced through its perineal canal and into her vagina to inspect vaginal walls, internal os of cervix, broad ligament and internal os of cervix for color, texture changes or evidence of inflammation or tumors.
Swab samples should be taken any time of month; however, during late estrus they are most sensitive. A guarded swab should also be collected with this sample to allow cytology assessment; otherwise it would be difficult to differentiate contaminants from pathogens without that process in place. Furthermore, it would allow assessment for potential trophoblastic formation.