Bacterial uterine infections in mares are a common cause of infertility and the major reason for decreased conception rates on foal-heat breedings. Bacterial contamination during intrauterine infusions for artificial insemination can also limit conception rates. Treatment so far has focused on hormonal manipulations to open the cervix and encourage drainage, plus intrauterine infusions and even systemic antibiotics.
A series of studies performed in Argentina showed excellent results when mares were treated either IV or by intrauterine infusion with an immune stimulant containing purified cell wall fractions from Mycobacterium species.
• Rapid clearance of bacteria after foaling with 65% conception rate on foal-heat breeding vs. 24% in placebo-treated mares, after a single intravenous treatment the day after foaling.
• With experimentally induced uterine Strep infection, IV treatment cleared the bacteria within 24 hours in 50% of the mares and within seven days in 70%. Intrauterine treatment cured the infection in 24 hours in 60%, with a final cure rate at seven days of 80%. The untreated control mares all remained infected during this time period.
• In mares prone to prolonged inflammatory reactions after breeding and AI, a single postbreeding IV treatment reduced the inflammatory response to normal in all treated mares.
Studies were all done on mares known by history and biopsy results to be prone/susceptible to uterine infections. The mycobacterium cell wall product used in these studies is made by Bioniche, and is the same active ingredient as in their Equimune product. The product, called Settle (www.expectbetterresults.com), is available through veterinarians in single-dose vials.
Note: The use of this product will not guarantee the mare clears an existing infection or avoids one. Follow-up exams and cultures are indicated in susceptible mares and may require further treatment.