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


     

J. Dairy Sci. 2009. 92:2706-2710. doi:10.3168/jds.2008-1775
© 2009 American Dairy Science Association ®
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Interpretive Summary
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
Google Scholar
Right arrow Articles by Okamura, C. S.
Right arrow Articles by Lucy, M. C.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Okamura, C. S.
Right arrow Articles by Lucy, M. C.

Short communication: Growth hormone receptor expression in two dairy breeds during the periparturient period

C. S. Okamura, J. F. Bader, D. H. Keisler and M. C. Lucy1

Division of Animal Sciences, University of Missouri, Columbia 65211

1 Corresponding author: LucyM{at}missouri.edu

The growth hormone receptor (GHR) 1A mRNA decreases after calving in the liver of Holstein dairy cows and may coordinate nutrient partitioning. The hypothesis that the decrease in GHR1A mRNA around the time of calving was characteristic of a second dairy breed was tested by examining Guernsey cows in addition to Holstein cows. Holstein and Guernsey cows were housed together and paired by parity and expected calving date. Liver biopsies and blood samples were collected prepartum (d –20 ± 1) and postpartum on d 3, and d 14 ± 1. The amounts of GHR1A, GHR1B, GHR1C, and insulin-like growth factor (IGF)1 mRNA were determined by quantitative reverse transcription polymerase chain reaction. Blood concentrations of growth hormone (GH) and IGF1 were measured by RIA. Both breeds underwent a decrease in GHR1A mRNA, a decrease in liver IGF1 mRNA, a decrease in blood IGF1, and an increase in blood GH after calving. The decrease in liver GHR1A and IGF1 mRNA after calving may be an inherent characteristic of dairy breeds that enables nutrient partitioning for greater milk production. Independent genetic selection in 2 dairy breeds seemingly exploited a similar mechanism, reduced GHR1A expression, to decrease blood IGF1 and increase blood GH, a key hormone involved in nutrient partitioning.

Key Words: growth hormone receptor • insulin-like growth factor 1 • dairy cow • nutrient partitioning






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2009 by the American Dairy Science Association ®.