Effect of Unilateral Ovariectomy on Reproduction and Induced Ovulation in Ewes

Abstract

The effects of unilateral ovariectomy on reproduction and hormone-induced ovulation was investigated in grade Rambouillet ewes. The 2-year lamb production of the unilaterally spayed ewes was significantly (P<.05) lower than that of the intact ewes. Removal of one ovary did cause a compensatory hypertrophy of the surviving gonad. The ovulation rate from the one ovary of the unilaterally castrated ewes was nonsignificantly lower than that from the two ovaries of the intact ewes. Injection of 1000 I.U. PMS caused a greater increase in ovarian weight during the normal breeding season than during seasonal anestrus. Administration of 1000 I.U. PMS significantly (P<.01) increased ovulation rate during the breeding season but not during the anestrous period. Copyright © 1967. American Society of Animal Science . Copyright 1967 by American Society of Animal Science