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Published on: November 28, 2018
Does the microbial flora in the ejaculate affect the freezeability of stallion sperm?
C Ortega-Ferrusola1, L González-Fernández, A Muriel
1Veterinary Teaching Hospital, Laboratory of Spermatology, University of Extremadura, Cáceres, Spain.
Reproduction in Domestic Animals = Zuchthygiene
|August 6, 2009
Summary
Equine ejaculate microbial flora impacts sperm cryopreservation. Bacteria like Klebsiella and Streptococcus correlate with sperm damage, affecting viability and motility post-thaw.
Area of Science:
- Veterinary Science
- Microbiology
- Reproductive Biology
Background:
- Sperm cryopreservation is crucial for equine breeding programs.
- Microbial contamination in ejaculate can negatively affect sperm quality.
- Understanding the impact of specific microbes is essential for improving freezing protocols.
Purpose of the Study:
- To investigate the relationship between microbial flora in stallion ejaculate and sperm cryopreservation success.
- To identify specific bacterial species associated with reduced post-thaw sperm quality.
Main Methods:
- Collected ejaculates from five stallions.
- Performed bacteriological analysis on pre-freezing aliquots.
- Froze ejaculates using a standard protocol.
- Assessed post-thaw sperm viability, motility (ALH), and caspase activity.
Main Results:
- Bacterial growth was present in all ejaculates.
- Klebsiella and beta-hemolytic Streptococcus correlated with increased dead spermatozoa and reduced sperm head lateral displacement (ALH).
- Corynebacterium correlated with increased sperm caspase activity, indicating apoptosis.
- Beta-hemolytic Streptococcus correlated with decreased low sperm caspase activity.
Conclusions:
- Microbial flora in stallion ejaculate can cause sublethal damage to spermatozoa during cryopreservation.
- Specific bacteria, including Klebsiella, Streptococcus, and Corynebacterium, are implicated in reduced sperm quality post-thaw.
- Managing microbial contamination is vital for optimizing equine sperm cryopreservation outcomes.
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