Ask Your Veterinarian Presented By Equistro: The Pesky Problem Of Yeast Infections In Broodmares

by | 12.10.2018 | 8:09pm

QUESTION: What is the most cost effective treatment for a mare with an intrauterine yeast infection? If not treated, will each cycle be difficult, possibly painful?

DR. ETTA BRADECAMP: While the most common causes of intrauterine infection in the mare are bacterial, cases of fungal endometritis occur at a much lower rate. The most common causes of these infections are Aspergillus and Candidia; however, many different species of fungal and yeast organisms have been identified as the cause of fungal endometritis in the mare.

Unfortunately, these types of infections can be difficult and costly to treat. Also, the organism identified, the duration of the infection, and the cause of the infection (which may be unknown or related to other pathologies of the reproductive tract) all affect how easy or difficult the infection is to treat. For this reason, there is no one treatment that will effectively treat all fungal/yeast endometritis cases. Therefore, when a mare is identified with an intrauterine fungal/yeast infection, the attending clinician bases the treatment protocol on the type of organism and its sensitivity to anti-fungal agents, combined with his or her knowledge of the duration of the infection and if it has been refractory to past treatments.

If not treated, the mare's chances of becoming pregnant with an ongoing fungal endometritis are almost zero. There are rare cases that have spontaneously resolved over time, typically from one season to the other when the mare was left untreated, but this is not recommended if the mare is intended to be used as a broodmare in the future. Left untreated, infection can become located deeper within the glands of the uterus and potentially form a biofilm, making it even more difficult to treat. Fortunately, if the decision is made to retire the mare and not treat the infection, the mares do not appear to show discomfort or pain associated with the fungal endometritis. 

Since there is no one treatment that effectively treats all fungal/yeast infections, the most cost effective one is one that is tailored for that specific case. Even when the appropriate effective anti-fungals are identified, the treatment may not be effective and the mare may need to be treated multiple cycles to eradicate the infection. A thorough exam of the reproductive tract, potentially including a hysteroscopic exam, may be necessary to identify underlying pathology that may predispose the mare to developing a yeast infection. If pathology, such as a cervical defect or poor perineal conformation, is identified, it is imperative that these problems are addressed prior to or in conjunction with the establishment of a treatment plan. Failure to address underlying pathology may result in failure of treatment protocols.

Dr. Etta Bradecamp

While some fungal/yeast infections are effectively treated with in a short period of time, many infections require a more protracted treatment of 10 to14 days that includes uterine lavage, the use of a broad spectrum anti-fungals such as betadine or hydrogen peroxide, and intrauterine and systemic anti-fungals selected based on sensitivity patterns of the causative agent. These longer, more intensive treatment protocols may cost upward of $1,000 per cycle and may need to be adjusted and repeated before the infection is resolved.  

Due to the complexity of fungal/yeast infections, it is recommended to treat them aggressively and thoroughly to maximize the chances of success. This includes identification of the causative agent, its sensitivity pattern and potentially biofilm properties, and performing ancillary tests to evaluate the mare's reproductive and overall health and rule out systemic disorders that may be immunosuppressive such as Cushings. Unfortunately, much more research is needed to identify which treatments are most effective for each type of fungal agent. Until then, clinicians must gather as much information possible for each case and if the initial treatment fails, evaluate where changes can be made to target the organism from a slightly different approach.

Dr. Etta Bradecamp graduated Veterinary School from Auburn University in 1999. She became an associate veterinarian at Keswick Equine Clinic in Virginia and resident at Goulburn Valley Equine Hospital in Victoria, Australia. Dr. Bradecamp joined the Rood & Riddle team in 2011 as an associate. Her areas of interest include the infertile mare, embryo transfer, assisted reproductive techniques (ART) and the problem stallion. In Dr. Bradecamp's free time, she enjoys running, riding, and traveling with her husband. 

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