A DYSTOCIA AND CESAREAN-SECTION MODEL TO CHARACTERIZE UTEROPLACENTAL PROSTAGLANDIN CONCENTRATIONS ASSOCIATED WITH RETAINED PLACENTA IN DAIRY-CATTLE

Plasma concentrations of prostaglandin F2a (PGF2a), 13,14-dihydro-15-k eto-prostaglandin F2a (PGFM), prostaglandin E2 (PGE2) and 13,14-dihydr o-15-keto-prostaglandin E2 (PGEM) were determined by RIA in blood samp les taken from the jugular vein and the uteroplacental circulation (um bilical vein, umbilical artery and uterine vein) of 13 Holstein Friesi an cows during caesarean section. According to discharge of placenta c ows were divided in 2 groups. Group I (shedding of placenta within 12 hours, NRP, n=8) and Group II (retained placenta, RP, n=5). In blood s amples taken from the jugular vein before surgery, no significant diff erences existed between groups regarding PGF2a, PGFM, PGE2 and PGEM. C oncentrations of PGF2a and PGFM in the uteroplacental circulation of N RP cows were significantly higher than those of RP cows (except for PG FM in the umbilical vein). For all sampling sites except the jugular v ein before surgery, PGE2 and PGEM levels of NRP cows were significantl y higher compared to RP cows.