Mares, adult female horses, are integral to the equine world, whether for breeding, sport, or companionship. Understanding mare anatomy, particularly the vulva, and reproductive health is essential for maintaining their well-being and ensuring successful breeding outcomes. One common issue affecting mares is pneumovagina, often referred to as “wind sucking,” and the solutions available to address it.
The vulva serves as the primary barrier protecting the mare’s reproductive tract from external contaminants. When this barrier is compromised, air and debris can enter, leading to irritation and inflammation of the vagina (vaginitis) and cervix (cervicitis). This can further progress to the uterus, causing endometritis (inflammation of the uterine lining) or placentitis (inflammation of the placenta) in pregnant mares. Moreover, the aspiration of bacteria or fungi can result in uterine infections, negatively impacting reproductive performance or, in severe cases, causing abortion.
Early detection of poor vulvar conformation is critical for preventing these complications. Older mares are frequently affected, often due to repeated foaling, perineal tissue damage, or poor body condition. As Dr. Jen Clulow notes, “Basically, things just aren’t as tight as they used to be!” Even if a mare hasn’t experienced problems in the past, conformational changes can occur over time, necessitating intervention. Younger mares with low body condition can also develop pneumovagina, sometimes identified in race training when it leads to decreased performance.
A common solution for poor vulvar conformation is the Caslick’s procedure. This surgical procedure involves suturing the edges of the vulval lips together to prevent air and fecal matter aspiration. The length of the closure depends on the individual mare’s conformation. Typically, the bottom third of the vulva remains open to allow normal urination.
The Caslick’s procedure is performed under local anesthesia. Sutures are usually removed after approximately 14 days, leaving a permanent seal. Due to the location, contamination is a risk, and breakdown of the Caslick’s can occur, so regular veterinary check-ups are essential to ensure the seal remains intact.
Important Considerations When a Mare Has a Caslick’s Procedure:
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Lifelong Requirement: Once a Caslick’s procedure is performed, the mare usually requires it for the remainder of her life because the natural vulvar structure is altered. This is a key consideration when acquiring a mare, especially a racing filly, with a Caslick’s in place.
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Breeding: A Caslick’s needs to be opened for natural breeding. While some stallions might be able to breed a mare with a Caslick’s in place, it’s generally necessary to open it. Artificial insemination can often be performed without opening the Caslick’s, either by breeding under the Caslick’s or through a speculum.
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Foaling: It is crucial to open a Caslick’s before foaling. The procedure creates a strong point in the vulva, and the foal will naturally take the path of least resistance. Failure to open the Caslick’s can lead to serious foaling complications and injury.
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Post-Foaling Repair: Even if a mare isn’t being bred in the current season, the Caslick’s should be repaired after foaling. This prevents uterine contamination during her time off.
The Caslick’s procedure helps restore the mare’s normal anatomy and plays a vital role in preventing endometritis and placentitis. This relatively simple surgical procedure can prevent the need for extensive uterine treatments and the potential loss of a valuable pregnancy. Instead of viewing a Caslick’s as a negative, it can be seen as a proactive step in protecting the mare’s reproductive health and future breeding potential. Taking preventive steps in mare care can help ensure their continued health.
