The Effect of Routine Postpartum Uterine Lavage on Endometrial Cytology, Culture, and Pregnancy Rates in Thoroughbred Broodmares.

The research piece examines the influence of postpartum uterine lavage on endometrial cytology, culture, and pregnancy rates in thoroughbred mares. The study found that though routine postpartum uterine lavage reduces the presence of certain cells in the endometrium at the time of first and second postpartum estrus, it doesn’t decrease endometrial culture rates or enhance pregnancy rates.

Study Design and Sample

• The retrospective study centered on 32 thoroughbred mares on a single farm in Australia in 2014 and 2015.
• The research split the two years into a control period (2014) where postpartum uterine lavage was not adopted and a treatment year (2015) where all mares received a uterine lavage 3 days postpartum.

Methodology

• The mares had their endometrial swabs taken during their first postpartum estrus (foal heat swab) and second postpartum estrus (second heat swab).
• This was to allow for culture and cytology prior to the mare being naturally bred at the second postpartum estrus.

Findings and Conclusion

• The research did not find a significant difference in the bacterial culture rates from foal heat or second heat swabs between the control and treatment years.
• The analysis of endometrial cytology of the foal heat swab and the second heat swab found a significantly higher percentage of polymorphonuclear cells (PMNs) in the control year in comparison with the treatment year.
• Positive culture and cytology rates were significantly higher at foal heat than at the second postpartum heat in both years.
• There was no association of the year, cytology, or culture with pregnancy rates.
• However, the study concluded that though routine postpartum uterine lavage significantly reduces the presence of endometrial PMNs at first and second postpartum estrus, it does not reduce endometrial culture rates or increase pregnancy rates.