Cervical mucus in estrous ewes after treatment with estrogen, progestogens and intrauterine devices.

The influence of estradiol, 6-alpha-methyl-17alpha-acetoxyprogesterone (MAP), and a unilaterally placed IUD on cervical mucus production was studied in estrous ewes. The animals received either 60 mg MAP from Days 9 to 21 of the extended estrous cycle, 25 mcg estradiol from Day 9 until estrus, or an IUD. MAP treatment significantly (p less than .05) increased cervical mucus production at estrus compared with the other treatments. However, the percentage of dry matter, chloride concentration, and spinnbarkeit did not markedly vary between groups. The protein content was markedly increased by estradiol. In a 2nd experiment, ewes received intravaginal sponges containing either 60 mg MAP, 30 mg 9-fluro-11beta-17-dihydroxyprogesterone-17-acetate (Cronolone), or 60 mg Cronolone from Day 9 to 21 of the extended estrous cycle. All 3 treatments significantly (p less than .01) increased cervical mucus production at estrus. There was little difference in the measured chemical and physical properties of cervical mucus between controls and treated animals. The increased production of cervical mucus in progesterone-treated animals may account for the reported reduction in the number of sperm in progesterone-treated ewes.