Presence and distribution of yeasts in the reproductive tract in healthy female horses.

The study investigates the presence and identification of yeast in the reproductive tracts of healthy female horses, concluding that Candida species, particularly C. krusei, are significant residents in these tracts, particularly relevant to empirical treatment decisions.

Research Objectives and Methods

• This study aimed to isolate and identify different types of yeasts found in the rear-end reproductive tract of healthy female horses. The main objective was to provide a better understanding of the normal yeast flora in these animals, which can be crucial information for treating reproductive tract infections.
• The researchers conducted a longitudinal study involving 151 horses from whom they collected a total of 453 samples using sterile swabs. The three different areas sampled were the vestibule, clitoral fossa, and vagina.
• These swabs were cultured on a specific type of agar suited for yeast growth and incubated for 7-10 days, after which the yeast colonies were observed and identified based on their unique physical characteristics and biochemical profiles.

Research Results

• The study found yeast colonies in 60 of the 151 horses. The yeast varieties belonged to nine different groups, with Candida spp. being the most common, forming 53.2% of the total yeast found. Other types included Cryptococcus spp., Saccharomyces spp., and more.
• Within the Candida species, C. krusei was the most commonly found, contributing 43.1% of all Candida colonies. There was a significant statistical difference observed in the prevalence of C. krusei compared to other Candida species.
• The study observed a higher concentration of yeast colonies in the vestibule area as compared to the vagina.
• Another significant finding was the higher isolation of yeast colonies from mares that had given birth multiple times, as compared to virgin mares.

Research Limitations and Conclusion

• The main limitation of this study comes from the predicament of differentiating between the yeast species that are normal residents in the horse reproductive tract, and those that may be potential pathogens, potentially leading to infections.
• Regardless, the study could successfully identify that Candida species, notably C. krusei, are significant residents of the caudal reproductive tract in healthy female horses.
• This finding has important implications for veterinarians and horse breeders, who might be required to prescribe empirical treatment before the complete culture results are available.