HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Trimberger, G. W. Search for Related Content PubMed Articles by Trimberger, G. W.

Menstruation Frequency and its Relation to Conception in Dairy Cattle¹

Dairy Husbandry Department, University of Nebraska, Lincoln

ABSTRACT

Observations as to the external evidence of the occurrence of menstruation were made at six different times daily on each of five days following estrus, for four lots of dairy females each consisting of 100 animals. One . hundred heifers and an equal number of cows were observed after estrus, when breeding did not occur, and 100 heifers and 61 cows showed evidence of menstruation. Two similar groups of 100 heifers and 100 cows were bred during estrus. Of the 100 heifers bred at estrus, 81 menstruated. Sixty-one of the heifers conceived and 52 or 85.25 per cent of those conceiving also menstruated while of the 39 that did not conceive, 29 or 74.36 per cent menstruated. Of the 100 cows bred at estrus, 61 menstruated. Seventy-two of these cows conceived, and 50 or 69.44 per cent of those conceiving; also menstruated, while of the 28 that did not conceive, 11 or 39.29 per cent menstruated. The data do not indieate any definite relationship between breeding and conception as affecting menstruation. When external evidences of menstruation were observed a total of 303 of the 400 individuals menstruated and 225 or 74.26 per cent showed this menstrual discharge on the second day following estrus.

¹ Submitted with the approval of Director of the Nebraska Agricultural Experiment Station Journal Series No. 289.