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Animal reproduction science2014; 145(1-2); 47-53; doi: 10.1016/j.anireprosci.2014.01.005

Removal of bacteria from stallion semen by colloid centrifugation.

Abstract: Bacteria (environmental contaminants and occasionally potential pathogens) are found in most stallion ejaculates and may negatively affect sperm quality during storage. Since the use of antibiotics can lead to the development of resistance, an alternative means of microbial control is desirable. The removal of bacteria from stallion semen using Single Layer Centrifugation through Androcoll-E was investigated. Known doses of cultured bacteria were added to freshly collected ejaculates (15mL aliquots) before processing by Single Layer Centrifugation. The resulting sperm pellets and controls (not processed by Single Layer Centrifugation) were cultured and the bacteria identified. In experiment 1, doses of E. coli from 2×10(2) to 2×10(7) colony forming units were added to aliquots of semen. In experiment 2, Taylorella equigenitalis or a mix of E. coli, Klebsiella pneumoniae and Streptococcus equi subsp. zooepidemicus (approximately 7×10(6), 5×10(6), and 6×10(6)cfu, respectively) were added to 15mL aliquots of semen. In experiment 1, more than 90% of the bacteria were removed where loading doses were >×10(4)cfu/mL. In experiment 2, varying proportions of different bacteria were removed, ranging from 68% for naturally occurring Corynebacterium spp. to >97% for added cultured E. coli. Thus, Single Layer Centrifugation can separate spermatozoa from many, but not all bacteria in stallion ejaculates and could be a useful alternative to adding antibiotics to semen extenders to control bacterial contamination. However, further research is needed to determine the effect of small numbers of bacteria on sperm quality.
Publication Date: 2014-01-17 PubMed ID: 24485764DOI: 10.1016/j.anireprosci.2014.01.005Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research analyzed the use of Single Layer Centrifugation (SLC) as an alternative method to antibiotics in removing bacteria from stallion semen, concluding that it was effective in removing a significant portion of the bacteria which can negatively impact sperm quality during storage.

Background of the Study

  • There is an inherent presence of environmental contaminants and potential pathogens, comprising mostly bacteria, in stallion semen. These bacteria can adversely affect the quality of sperm during storage.
  • Antibiotics have been commonly used to combat this bacterial presence; however, the continuous use of antibiotics can potentially lead to the development of antibiotic resistance. Hence, the study sought to find an alternative method for microbial control.

Research Process and Experiment Design

  • The study focused on applying a specific centrifugation process known as Single Layer Centrifugation (SLC) using Androcoll-E to remove bacteria from the semen.
  • Cultured bacteria were intentionally added to fresh ejaculates before proceeding with the SLC processing. The resultant sperm pellets were subjected to Culturing and Identification of the bacteria.
  • The spiking of semen was done in two rounds of experiment:
    • Experiment 1: Doses of bacteria called E. coli, ranging from 2×102 to 2×107 colony-forming units (cfu), were added.
    • Experiment 2: Bacteria, including Taylorella equigenitalis or a combination of E. coli, Klebsiella pneumoniae, and Streptococcus equi subsp. zooepidemicus, were added in specific quantities.

Results and Conclusion

  • In Experiment 1, more than 90% of the bacteria were removed where the loading dose was >x104 cfu/mL.
  • In Experiment 2, varying proportions of different bacteria were removed, which ranged from 68% for naturally occurring Corynebacterium spp. to >97% for added cultured E. coli.
  • The results demonstrate that SLC can separate spermatozoa from several, but not all, bacteria in stallion ejaculates, thus revealing the potential of SLC as a practical alternative to the addition of antibiotics to control bacterial contamination in semen extenders.
  • The research, however, calls for additional studies to determine the effects of residual bacteria on sperm quality.

Cite This Article

APA
Morrell JM, Klein C, Lundeheim N, Erol E, Troedsson MH. (2014). Removal of bacteria from stallion semen by colloid centrifugation. Anim Reprod Sci, 145(1-2), 47-53. https://doi.org/10.1016/j.anireprosci.2014.01.005

Publication

ISSN: 1873-2232
NlmUniqueID: 7807205
Country: Netherlands
Language: English
Volume: 145
Issue: 1-2
Pages: 47-53

Researcher Affiliations

Morrell, J M
  • Swedish University of Agricultural Sciences, Uppsala, Sweden. Electronic address: jane.morrell@slu.se.
Klein, C
  • Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, USA.
Lundeheim, N
  • Swedish University of Agricultural Sciences, Uppsala, Sweden.
Erol, E
  • University of Kentucky Veterinary Diagnostic Laboratory, Lexington, USA.
Troedsson, M H T
  • Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, USA.

MeSH Terms

  • Animals
  • Bacteria / isolation & purification
  • Centrifugation / methods
  • Colloids / pharmacology
  • Decontamination / methods
  • Ejaculation
  • Horses
  • Male
  • Microbiological Techniques / methods
  • Semen / microbiology
  • Semen Analysis

Citations

This article has been cited 18 times.
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