Plasma concentrations of 13,14-dihydro-15-ketoprostaglandin F2 alpha in mares during uterine involution.

The article explores a study on postnatality uterine involution process in mares, monitored alongside levels of 13,14-dihydro-15-keto-PGF2 alpha, revealing no significant correlation between the two.

Objective and Process

• The purpose of this research was to delve into the uterine involution process in mares after giving birth, and its correlation with 13,14-dihydro-15-keto-PGF2 alpha (a metabolite of prostaglandin F2 alpha known as PGFM) concentrations in the blood plasma.
• The study consisted of twelve mares that were allowed to give birth naturally. Post parturition, each mare’s internal genital tract was assessed manually and ultrasonographically every 48 hours starting from day 3.

Observations and Findings

• It was noted that by the 5th day, there were no differences in size between gravid and nongravid uterine horns (indicating the uterus returning to its non-pregnant size), and by day 7, there was no detection of uterine fluid.
• On day 7, samples for histologic evaluation were collected via endometrial biopsy and uterine swab specimens for microbiologic culture. Some level of bacteria was present in the uterus of ten out of twelve mares. Eight out of the twelve mares had their uteri histologically involuted (returned to its normal, non-pregnant state) by day 7.
• All mares showed signs of ovulation between 7 to 12 days after parturition.

PGFM Measurements

• Concentrations of PGFM were monitored and recorded through daily blood plasma samples obtained from the mares’ jugulars for three weeks after parturition. The levels of PGFM were found to be low on the day following parturition.
• Interestingly, there was no significant correlation found between uterine involution and PGFM concentrations in the mares.

Reproductive Performance Post-Parturition

• All twelve mares were bred at their first estrus after parturition, and nine of them became pregnant demonstrating a successful return to fertility.

Conclusion

• The findings suggest that, in the case of the mares studied, PGFM concentrations weren’t necessarily indicative of the progression of uterine involution. This research provides essential insights into the post-partum recovery period in mares, including the process of uterine involution and the return of fertility.