Concentrations of 15-keto-13, 14-dihydro-prostaglandin F2 alpha in the mare during spontaneous and oxytocin induced foaling.

The study measured the changes in plasma 15-keto-13, 14-dihydro-prostaglandin F2 alpha in mares before, during, and after both spontaneous and oxytocin-induced deliveries. It was found that there was an increase in prostaglandin levels around delivery time regardless of delivery type, but no increase in the last 10 days of gestation.

Objective of the Study

• The purpose of the study was to detect any increase in the concentrations of the plasma 15-keto-13, 14-dihydro-prostaglandin F2 alpha in mares during their final gestation period, and during and after birth—whether spontaneous or oxytocin-induced.

Procedure of the Study

• Three mares going through spontaneous deliveries and eight mares undergoing oxytocin-induced deliveries were closely monitored
• The investigators monitored the plasma 15-keto-13, 14-dihydro-prostaglandin F2 alpha concentration frequently during multiple stages—before, during, and after the delivery.

Findings of the Study

• There was no observed increase in the concentration of the aforementioned prostaglandin metabolite during the last 10 days of gestation in the mares.
• For mares delivering spontaneously, there was a significant increase in the level of the prostaglandin metabolite, with concentrations rising from 3 ng/ml to 182 ng/ml close to the delivery.
• After delivery, the prostaglandin metabolite concentrations fell rapidly.
• There were observed increases in the prostaglandin levels on days 1 and 3 post-partum.
• In mares induced with oxytocin, the maximum concentrations were seen around the time of delivery, and considerable elevations were noticed as early as 2 minutes post-oxytocin injection.

Significance of the Findings

• The changes in plasma 15-keto-13, 14-dihydro-prostaglandin F2 alpha observed in the study are likely significant in relation to parturient and post-parturition events and any associated changes in the levels of the hormone relaxin that occur at the same time.
• The observations provide insight into the biochemical changes mares undergo during and after both spontaneous and induced delivery, which could be significant for improved reproductive health management of horses in future.