Journal of Dairy Science Vol. 31 No. 12 1032-1040
© 1948 by American Dairy Science Association ®
Some Factors Influencing the Male Hormone Content of Cow Manure1
C. W. Turner
Department of Dairy Husbandry, University of Missouri, Columbia
ABSTRACT
- Manure from cows of the Guernsey, Holstein and Jersey breeds during various physiological states has been, dried at 45° C. and assayed biologically for its content of male (androgenic) hormone.
- It was observed that sexually mature non-pregnant heifers excrete male hormone at a level comparable to those of mature cows.
- During the first two-thirds of pregnancy, no tendency for a rise in androgen excretion was observed. There was evidence of a preparturient rise in androgens.
- With the advance of lactation, no change in androgen excretion was noted except when associated with the approach of the subsequent parturition.
- Dried cow manure from the Guernsey and Holstein breeds appeared comparable in biological activity; the Jersey cows appeared to excrete slightly more male hormone.
- It is suggested that the preparturient rise in androgen may be related to the marked rise in estrogen at the same time.
- It is possible that androgens as well as estrogens play roles in the stimulation of the secretion of the lactogenic hormone by the pituitary at the time of parturition.
FOOTNOTES
1 Contribution from the Department of Dairy Husbandry, Missouri Agricultural Experiment Station, Journal Series No. 1120.
Copyright © 1948 by the American Dairy Science Association ®.