JDS
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Journal of Dairy Science Vol. 54 No. 11 1669-1674
© 1971 by American Dairy Science Association ®
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Garverick, H. A.
Right arrow Articles by Cunningham, M. D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Garverick, H. A.
Right arrow Articles by Cunningham, M. D.

Dietary Urea for Dairy Cattle. I. Relationship to Luteal function1

H. A. Garverick2, R. E. Erb, R. D. Randel3 and M. D. Cunningham

Department of Animal Sciences, Purdue University, Lafayette, Indiana 47907

ABSTRACT

Isonitrogenous complete mixed rations containing concentrates, corn silage, and ground corn cobs, differing only in source of supplemental nitrogen (Group I—soybean meal and Group II—urea), were fed to Holstein-Friesian heifers for a minimum of 60 days. The purpose was to study the effect of dietarv urea on luteal function. Jugular blood and corpora lutea were collected on Day 12 after estrus. Average concentrations of progesterone, luteinizing hormone, corticosterone, and cortisol in blood plasma were approximately the same for both groups. Ten corpora lutea from Group I were heavier (P < .005) than the 12 from Group I1 (6.4 ± .6 g versus 4.3 ± .3 g). The corpora lutea from Group I1 were softer and more fragile than those from Group I, but there were no discernible histological differences. The contents and concentrations of progesterone and 20ß-hydroxy-pregnene-3-one in unincubated corpora lutea were not significantly different between treatments. However, corpus luteum tissue from Group I as compared to Group I1 synthesized more progesterone (P < .05) during in vitro incubation in blood plasma (2 hr at 37 C) and contained more total progesterone (P < .05) after incubation. Source of jugular plasma substrate, either from Group I or Group 11, had no significant effect on synthesis of progesterone. The relationship between differences in corpus luteum function due to ration and reproductive efficiency was not determined.

FOOTNOTES

1 Journal Paper 4434, Purdue University Agricultural Experiment Station.

2 Fellow, Allied Chemical Foundation, New York City. Present address: Department of Dairy Husbandry, University of Missouri, Columbia 65201.

3 Present address: United States Department of Agriculture Range Livestock Experiment Station, Miles City, Montana 59301.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1971 by the American Dairy Science Association ®.