Effect of charcoal-treated bovine follicular fluid on secretion of LH and FSH in ovariectomized heifers.

Abstract

The objective of the experiment was to determine whether pools of charcoal-treated bovine follicular fluid (bFF) removed from large (greater than 10 mm) follicles during the preovulatory (d 18 to 1), postovulatory (d 2 to 6) or mid-cycle (d 7 to 17) stages of the bovine estrous cycle altered secretion of luteinizing hormone (LH) or follicle-stimulating hormone (FSH) in ovariectomized heifers. After a 20-ml injection of bFF given at three consecutive 6-h intervals, secretion of FSH was depressed from approximately 116 to 53 ng/ml by each pool of bFF. In contrast, bFF did not affect secretion of LH. Serum from an ovariectomized cow (control) had no effect on secretion of LH or FSH. We concluded that bFF contained a nonsteroidal component (perhaps inhibin) that suppressed FSH secretion in heifers.