Enzyme Activities and Protein and Carbohydrate Concentrations in Cervical Secretions at Dioestrus in Normal Ewes and Ewes With Permanent Phytooestrogenic Infertility

Abstract

Cervical secretions of clover-affected and control ewes in the luteal phase of the ovarian cycle were obtained by flushing the anterior vagina. The flushings were analysed for proteins, carbohydrates and enzyme activities, and were found to be similar to the secretions of the normal ovine uterus. There was significantly more protein, carbohydrate and acid-soluble glycoprotein but less alkaline phosphatase, N-acetylglycosidases (EC 3.2.1.30 and 3.2.1.53) and ribonuclease I in the vaginal flushings of clover-affected ewes.The observed changes were not due to more inflammation in the cervix of clover-affected ewes as there were fewer bacteria, leukocytes and epithelial cells and no elevation of lysozomal enzyme activities in their flushings. It is suggested that the cervix of the clover-affected ewe behaves as though under a stronger than normal oestrogenic stimulation during dioestrus. IntroductionEwes rendered permanently infertile by prolonged ingestion of oestrogenic clover produce abnormal cervical mucus which prevents normal sperm transport and fertilization (Lightfoot et al. 1967;Smith 1971). Histological changes of the cervices of these ewes have also been observed by Heydon and Adams (1977). A test on cervical secretions could be expected to be a useful diagnostic method for detecting permanent clover infertility.Adams (1967a) found that mucus from clover-affected ewes had a spinnbarkeit value significantly lower than that from control ewes. Although the mucus spinnbarkeit test was subsequently found to be useful for assessing lowered reproductive performance in ewes exposed to oestrogenic pasture (Adams 1977), it has limitations. Spinnbarkeit varies with the time of the breeding season so that adjustment is needed to compare results obtained at different times. Cervical mucus is abundant only when the ewe is in oestrus and even then some ewes produce so little that collection of an adequate sample is impossible. Because of these limitations it is worthwhile to seek other diagnostic methods and one possible area is the biochemical analysis of cervical secretions during the luteal phase of the reproductive cycle.In the present experiment proteins, carbohydrates and some enzymes, including lysozomal enzymes, in the. luteal-phase cervical secretions obtained by flushing the anterior vagina of clover-affected and control ewes were assayed and compared.

Changed control of cervical secretion from infertile ewes previously exposed to oestrogenic clover pasture

“…1). Such autonomous production is consistent with previous findings on intact ewes at dioestrus (Tang & Adams, 1978) and with the rate of protein and glycoprotein synthesis being greater in the cervix of ovariectomized clover-affected ewes than in controls (Tang mucus can be understood as part of the basic change that occurs in ewes with clover disease. As described in the 'Introduction', a number of lines of evidence indicate that prolonged exposure to phyto-oestrogens can produce 'organizational' effects on the ewe akin to those normally produced by steroidal oestrogens during fetal life (Adams, 1981a).…”

Proportions of Nucleic Acids in the Uteri of Ewes with Clover Disease and the Effect of Oestrogen after Ovariectomy

“…In affected ewes on non-oestrogenic pasture, the cervix continues to act as though it is under oestrogenic stimulation during dioestrus (Tang and Adams 1978). Ovariectomized-affected ewes have an impaired responsiveness to repeated treatment with oestradiol benzoate which prevents the production of cervical mucus with a normal spinnbarkeit (Adams 1979) and the responsiveness of the hypothalamus to oestrogen is also slightly decreased (Adams 1978).…”