ASSOCIATIONS AMONG PROSTAGLANDIN-F2ALPHA, PLASMA ZINC, COPPER AND IRON CONCENTRATIONS AND FETAL LOSS IN COWS AND MARES

The objective of this study was to test the hypothesis that PGF2alpha is associated with abortion and changes in plasma Zn, Cu, and Fe conce ntrations in cows and mares in their first trimester of pregnancy. Ele ven pregnant cows were infused with endotoxin (n=5) or endotoxin plus an inhibitor of cycloxygenase, flunixin meglumine (n=6). Blood was col lected over a 5-d period. Additionally, 4 mares were treated every 24 h with cloprostenol sodium and blood was collected hourly until aborti on. Plasma Zn, Cu, and Fe were determined. Three of five cows treated with endotoxin aborted, but none of the six cows treated with endotoxi n and flunixin meglumine aborted. Aborting cows had lower plasma Zn (P = 0.048) over the 5-d study period compared with the nonaborting cows . The changes in Zn corresponded to release of PGF2alpha. All 4 mares aborted and plasma Zn concentrations were lower (P = 0.008) and Cu/Zn was higher (P = 0.02) 12 h after cloprostenol treatment. Plasma Zn may be a useful biomarker for risk of spontaneous abortion, and the decli ne in plasma Zn may be caused by PGF2alpha.