Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School



The cervix is a thick walled tube between the vagina and the uterus which serves as a passageway for sperm to enter and for the products of birth to be expelled. Several investigators have reported that realxin causes an observable and measureable cervical dilation. Whether this hormone, which has been assayed only in the pregnant female of both humans and animals, is the one which initiates and facilitates the birth process has yet to be determined. The purpose of this study was to make histological and histochemical comparisons of the effects of relaxin alone and in combination with the sensitizing agents, di-ethly stilbesterol and progesterone, on the cervix of the nongravid bovine. The results were then compared with normal, nonsensitized, nongravid bovine cervical tissue and with bovine cervical tissue following parturition. The mechanism for cervical dilatability is the elongation of the muscle cells and a change in form from a spindle shape with tapered ends to an elongate fibrous strand of uniform diameter. This change is accompanied by separating the cells as a result of inhibition of great amounts of fluid.

Library of Congress Subject Headings

Veterinary obstetrics


Includes bibliographical references



Number of Pages



South Dakota State University