Presence and distribution of fungi and bacteria in the reproductive tract of healthy stallions.

This research study aimed to explore and describe the distribution of fungi and bacteria in the reproductive tract of healthy, fertile stallions. Results showed significant differences in the presence of filamentous fungi in various parts of the tract, and that some bacteria were always present at all locations, including in ejaculate. The study contributes to existing knowledge about the microbial flora in the stallion reproductive tract.

Objectives and Methodology

• The primary objective of the study was to gain more understanding about the distribution of fungi and bacteria in the genital apparatus of stallions. This was due to the significant role that microorganisms play regarding fertility in mares.
• The researchers studied a sample size of 11 healthy, fertile stallions. From each stallion, they collected samples from five different locations within the reproductive tract, namely the urethral fossa, the penis/internal lamina of the prepuce, the urethra pre-ejaculation, the urethra post-ejaculation, and semen.
• For fungal examination, three sets of samples were taken (totaling 165), while for bacterial examination, one set of samples were taken (55 total).

Key Findings

• There was a statistical difference observed in the presence of filamentous fungi – it was higher in the urethral fossa or penis/prepuce (45.4%) and lower in urethra pre- or postejaculation or semen (15.1%, 6.0%, and 0.0% respectively).
• Yeasts were only found in 9.1% of the samples and never in semen. The most common fungi found were Penicillium spp., Aspergillus spp., Scopulariopsis spp., Trichosporon spp., and Mucoracee.
• The study revealed that the bacterial count equal to or more than 10,000 colony forming units (CFU) was higher in the urethral fossa than in the urethra pre- or postejaculation or in semen.
• Some bacterial growth was noted in all locations, including in the ejaculate. The locations also showed differences in the presence of Staphylococci, both coagulase positive and negative.
• Certain pathogenic species including Salmonella enterica Abortus equi and sulphite reducing clostridia, Klebsiella spp. and Pseudomonas spp. were never isolated.
• Escherichia coli and coliforms consistently displayed a low or non-existent flora.

Significance and Contribution to the Literature

• The research provides valuable insights into the microbial distribution in the reproductive tract of stallions that adds to existing literature in the field.
• The findings lend themselves to a better understanding of stallion health and fertility, and how the microbial presence may affect these.