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

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

Developmental Changes in the Kinetics of Glucose and Urea in Holstein Calves

H. Hayashi^*,1, M. Kawai^*, I. Nonaka, F. Terada, K. Katoh^* and Y. Obara^*

^* Department of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori, Aoba-ku, Sendai, 981-8555, Japan
Department of Animal Physiology and Nutrition, National Institute of Livestock and Grassland Science, 2 Ikenodai, Tsukuba City, Ibaraki, 305-0901, Japan

¹ Corresponding author: hhayashi{at}rakuno.ac.jp

Because weaning is the point when the nutrient composition of feed changes for the neonatal ruminant, the present experiment was conducted to assess the developmental changes in the kinetics of glucose and urea over this period, using stable isotopes of glucose and urea, at 4, 13, and 24 wk in calves. Plasma concentrations of nonesterified fatty acids, amino-N, urea-N, and insulin-like growth factor-I increased, but that of growth hormone decreased with age. The plasma glucose concentration increased at 13 wk of age and thereafter decreased at 24 wk of age. The glucose irreversible loss and recycling rates were significantly higher at 4 wk of age than at 13 and 24 wk of age. On the other hand, the irreversible loss and recycling rates of urea, as well as the urea pool size, were higher at 24 wk of age than at 4 and 13 wk. It is concluded that weaning at 6 wk is the pivotal time for the alteration of glucose kinetics. However, the aging process, but not weaning, is important for changes in the kinetics of urea in calves.

Key Words: glucose kinetics • urea kinetics • aging • calf

This article has been cited by other articles:

				S. Haga, S. Fujimoto, T. Yonezawa, K. Yoshioka, H. Shingu, Y. Kobayashi, T. Takahashi, Y. Otani, K. Katoh, and Y. Obara Changes in Hepatic Key Enzymes of Dairy Calves in Early Weaning Production Systems J Dairy Sci, August 1, 2008; 91(8): 3156 - 3164. [Abstract] [Full Text] [PDF]

				M. Takagi, T. Yonezawa, S. Haga, H. Shingu, Y. Kobayashi, T. Takahashi, Y. Ohtani, Y. Obara, and K. Katoh Changes of activity and mRNA expression of urea cycle enzymes in the liver of developing Holstein calves J Anim Sci, July 1, 2008; 86(7): 1526 - 1532. [Abstract] [Full Text] [PDF]

				G. I. Zanton and A. J. Heinrichs Analysis of Nitrogen Utilization and Excretion in Growing Dairy Cattle J Dairy Sci, April 1, 2008; 91(4): 1519 - 1533. [Abstract] [Full Text] [PDF]

				H. Shingu, H. Hayashi, E. Touno, A. Oshibe, S. Kushibiki, S. Oda, K. Katoh, and Y. Obara Characteristics of developmental changes in the kinetics of glucose and urea in Japanese Black calves: Comparison with Holstein calves J Anim Sci, November 1, 2007; 85(11): 2910 - 2915. [Abstract] [Full Text] [PDF]

				G. I. Zanton, M. T. Gabler, and A. J. Heinrichs Manipulation of Soluble and Rumen-Undegradable Protein in Diets Fed to Postpubertal Dairy Heifers J Dairy Sci, February 1, 2007; 90(2): 978 - 986. [Abstract] [Full Text] [PDF]