Fourteen ewes were isolated from contact with rams for 30 days and primed for 6 days with an intravaginal sponge containing 60 mg of MAP during the nonbreeding season; rams were introduced at sponge withdrawal. A) FSH (-■-) and LH levels (-▲-) normalized to the LH surge (n = 10). B) FSH levels in E-O (-■-, n = 5), NE-O (-▲-, n = 5), and NE-NO (-◆-, n = 4) ewes. (BR = data pooled from the period before the introduction of the rams.) (Time with respect to the sponge withdrawal is equal to the time for ram's introduction.) E-O ewes displayed estrous behavior and ovulated after introduction of the rams, NE-O ewes ovulated but did not come into estrus, and NE-NO ewes neither ovulated nor came into estrus.