Fate of the Two Largest Follicles in the Ewe after Injection of Gonadotrophins at Two Stages of the Estrus Cycle

Abstract

Summary

The response of the two largest follicles, identified at Day 10 or Day 14 of the estrous cycle in ewe, was determined by injecting exogenous gonadotrophins. The largest follicle marked on the 10th day of the estrus cycle ovulated only when the ewes were given gonadotrophins (control 0/5; treated 4/5), while when marked on the 14th day, it did not require gonadotrophin injection to ovulate (control 4/5; treated 3/ 4). The second largest follicle marked on the 10th or 14th day ovulated in 60% and 50% of the treated ewes respectively, while nontreated ewes did not ovulate any of the second largest follicles at the ensuing estrus.