EFFECTS OF ESTROGEN AND PROGESTERONE UPON THE GENITAL TRACT OF THE EWE1

Abstract

30 yearling ewes were spayed and, following recovery, were treated to demonstrate the effects of estrogen and progestin upon the sexual activity and histology of the reproductive tract. 4 of the spayed ewes received no inj.; 5 received Progynon-B (Schering Corporation) and were killed 12 days after injs.; 4 received Progynon-B alone, but were killed 2-3 days after injs. while showing signs of heat; and 14 ewes received Progynon-B, following which they were divided into 3 groups and administered different doses of progesterone. Typical signs of estrus were produced in virtually all of the ewes by the inj. of Progynon-B. Vaginal smear records taken on the ewes showed no difference between the smears of spayed ewes given Pro-gynon-B alone and Progynon-B followed by progesterone. Progynon-B caused an increase in the height of the vaginal, cervical, and uterine (both surface and glandular) epithelium. Injs. of progesterone following a Progynon-B injection tended to maintain the increased height, particularly in the cervix and uterus. The addition of progesterone, even at the lower levels, caused an increase in the amt. of uterine gland coiling. An increased amt. of thick, dark staining mucus was seen in the cervical sections of those spayed ewes given Progynon-B plus the high level of progesterone.