USE OF PLASMA-CONCENTRATIONS OF 13,14-DIHYDRO,15-KETO-PGF2-ALPHA (PGFM) IN THE DIAGNOSIS OF SUBCLINICAL ENDOMETRITIS AND ITS RELATIONSHIP TO FERTILITY IN THE POSTPARTUM DAIRY-COW

The objective of this study was to determine the value of using plasma concentrations of PGFM to diagnose subclinical endometritis in the da iry cow, and its relationship to subsequent fertility. A total of 274 cows between 24 to 29 d post partum was divided into 4 groups on the b asis of clinical features of the uterus and ovary. Cows in Group 1 (n= 74) had a normal, involuting uterus and a CL on the ovary; cows in Gro up 2 (n=51) had a normal, involuting uterus but no CL on the ovary; co ws in Group 3 (n=83) did not have a normal, involuting uterus but had a CL on the ovary; and cows in Group 4 (n=66) did not have a normal, i nvoluting uterus or a CL on the ovary. A blood sample was obtained fro m each cow on the day they were placed on the study, and plasma concen trations of PGFM and P4 were determined using RIA. Cows were artificia lly inseminated (AI) at the first observed estrus after Day 60 post pa rtum, and pregnancy was determined by palpation of the uterus per rect um between 45 and 50 d postAI. Reproductive responses evaluated were c onception rate to first service, days open, and percentage of cows pre gnant by 90, 120, 150 and 180 d post partum. Data were analyzed using GLM procedures of SAS and a 2x2 factorial with contrast procedures. Po lynomial regression analysis was used to determine the shape of the PG FM, P4 and fertility curves. There was no difference among mean PGFM c oncentrations of cows in each group. The rate of decline of plasma PGF M concentrations was lower in cows with an abnormal uterus and a CL on the ovary compared with those without a CL. A lower percentage of cow s with abnormal uteri was pregnant by 90 d post partum compared with c ows with normal uteri. From the results of this study, it was conclude d that plasma PGFM concentrations between Days 24 to 29 post partum we re not effective in identifying cows with subclinical endometritis. (C ) 1998 by Elsevier Science Inc.