Variations in certain properties of bovine cervical mucus during the oestrous cycle.

THE epithelium of the cervix and upper vagina of the cow and certain other animals produces a mucous secretion in which, according to Woodman & Hammond [1925], may be found a mucoprotein belonging to the class of mucin bodies containing mucoitin sulphuric acid, since they identified glucosamine in a specimen of cervical mucus. The chemical composition of this secretion does not appear to have been further investigated since this observation was made, but the scanty evidence available indicates that it may contain a mucopoly-saccharide-protein complex (see Meyer's [1938] classification of mucopoly-saccharides and glycoproteins). Changes in the amount and physical properties of bovine cervical mucus were described by Woodman & Hammond [1925], who pointed out that at oestrus the secretion is plentiful, fairly fluid and capable of being drawn out into threads, whereas after oestrus it is considerably diminished in amount and less fluid. The amount of secretion, however, differs markedly in different animals and cannot be taken as a definite indication of oestrus. In pregnancy the secretion is very thick and adhesive, effectively sealing the gravid uterus, and Marshall & Hammond [1937] have described a rough, subjective test for pregnancy in the cow based on recognition of the characteristic stickiness 'of the cervical secretion. The work described in this paper forms part of a study of the chemical and rheological properties of bovine cervical mucus in different phases of the reproductive cycle, undertaken with a view to attempting to develop the mucin test of Marshall & Hammond [1937] into an objective test for early pregnancy in the cow. As a first step it was considered ilecessary to study the changes in the properties of the secretion during the oestrous cycle in order to provide a standard with which to compare the behaviour of these properties during pregnancy. As has been Zhortly described in a preliminary note [Scott Blair et at. 1941], these studies have led to the development of a simple and rapid rheological test for oestrus or near-oestrus which may prove useful in the diagnosis of bovine oestrus in cases, and these are not infrequent [see Hammond, 1927], in which the external signs are not obvious even to a skilled herdsman, and also for predicting its imminence when, as in cold winter weather, it is to be expected that it may be easily missed on account of its short duration, particularly when it occurs at.night. Such studies might also …