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Home / Equine Research Bank / Theriogenology / Relationships between uterine culture, cytology and pregnanc...
Theriogenology2007; 68(3); 395-402; doi: 10.1016/j.theriogenology.2007.05.050

Relationships between uterine culture, cytology and pregnancy rates in a Thoroughbred practice.

Abstract: Endometrial cytology and culture specimens (n=2123) were collected concurrently with a guarded uterine culture instrument from 970 mares (738 barren, 1230 foaling and 155 maiden mares) during three breeding seasons (2001-2004). Results were compared to the 28-d pregnancy rate for the cycle from which the samples were taken. Cytological smears were evaluated for inflammation at x100 and graded as: not inflammatory (0-2 neutrophils/field), moderate inflammation (2-5 neutrophils/field), severe inflammation (>5 neutrophils/field), or hypocellular (scant epithelial cells and no neutrophils). Uterine culture swabs were plated within 6h, incubated for 72 h and results determined at 24, 48, and 72 h. Approximately, 20% (n=423) cytology samples were positive for inflammation (>2 neutrophils), whereas approximately 11% (n=231) of cultures had microorganisms recovered. A majority (64%) of the positive cultures (147/231) had inflammation on cytology smears. Streptococcus equi subsp. zooepidemicus was associated with more positive cytology results than coliforms (P<0.01). Mares with positive cytology or culture had lower pregnancy rates than mares with normal findings (P<0.01). Lowest pregnancy rates were recorded for mares with severe endometrial inflammation (21%, versus moderate inflammation 48%). Isolation of a microorganism from mares with endometrial inflammation was not associated with a further reduction in pregnancy rates. In barren, foaling and maiden mares, cytology was positive in 28, 17, and 5%, respectively, and culture was positive in 12.2, 11.1, and 3.2%. Foaling and maiden mares had higher pregnancy rates than barren mares (62, 69, and 44%, respectively, P<0.001). In conclusion, a positive cytology was twice as common as a positive culture, and isolation of microorganisms was associated with reduced pregnancy rates, even in the apparent absence of inflammation.
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Publication Date: 2007-06-21 PubMed ID: 17583785DOI: 10.1016/j.theriogenology.2007.05.050Google Scholar: Lookup
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  • Journal Article

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.

This study explores the connections between uterine inflammation, presence of bacteria, and pregnancy rates in thoroughbred horses. It reveals that mares with uterine inflammation or bacterial presence have lower chances of pregnancy, while the intensity of inflammation can further decrease these rates.

Background

  • The research investigated the links between the results of endometrial cytology and culture specimens, and successful pregnancy rates in thoroughbred mares.
  • The study spanned three breeding seasons from 2001 to 2004 and covered 970 mares of different types – barren, foaling, and maiden.

Methodology

  • Endometrial cytology and culture specimens were collected using a guarded uterine culture instrument.
  • The cytological smears were scanned for signs of inflammation and graded accordingly, while the culture swabs were examined for the presence of microorganisms.

Results

  • 20% of the cytology samples showed evidence of inflammation, while just 11% of the cultures showed signs of microorganisms.
  • Around 64% of the positive cultures showed inflammation in the cytology smears. The bacteria Streptococcus equi subsp. zooepidemicus was found to be more associated with positive cytology results than coliforms.
  • Mares with positive cytology or positive culture had lower pregnancy rates compared to those with normal findings.
  • The lowest pregnancy rates were found in mares with severe uterine inflammation.
  • The presence of microorganisms did not lead to a further decrease in pregnancy rates in mares with endometrial inflammation.

Conclusion

  • In conclusion, the study found that a positive cytology was twice as common as a positive culture, indicating that inflammation is more prevalent than bacterial infection.
  • Also, the isolation of microorganisms was linked to reduced pregnancy rates, even when there was no visible inflammation.
  • The researchers recommend further investigation into the effects of specific types of bacteria and the role they play in equine reproduction.

Cite This Article

APA
Riddle WT, LeBlanc MM, Stromberg AJ. (2007). Relationships between uterine culture, cytology and pregnancy rates in a Thoroughbred practice. Theriogenology, 68(3), 395-402. https://doi.org/10.1016/j.theriogenology.2007.05.050

Publication

Theriogenology
ISSN: 0093-691X
NlmUniqueID: 0421510
Country: United States
Language: English
Volume: 68
Issue: 3
Pages: 395-402

Researcher Affiliations

Riddle, W T
  • Rood and Riddle Equine Hospital, and Department of Statistics, University of Kentucky, Lexington, KY 40506-0027, USA. triddle@roodandriddle.com
LeBlanc, M M
    Stromberg, A J

      MeSH Terms

      • Animals
      • Breeding
      • Endometritis / diagnosis
      • Endometritis / microbiology
      • Endometritis / veterinary
      • Endometrium / cytology
      • Endometrium / microbiology
      • Female
      • Horse Diseases / diagnosis
      • Horse Diseases / microbiology
      • Horses
      • Neutrophils / cytology
      • Pregnancy
      • Pregnancy Rate
      • Retrospective Studies
      • Streptococcus equi / isolation & purification
      • Uterus / cytology
      • Uterus / microbiology
      • Uterus / physiology

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