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 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 Oldham, J. D. Search for Related Content PubMed PubMed Citation Articles by Oldham, J. D.

Protein-Energy Interrelationships in Dairy Cows

National Institute for Research in Dairying, Shinfield, Reading RG2 9AT

ABSTRACT

In dairy cows two distinct and important aspects of the interrelationship between protein and energy-yielding nutrients can be identified. First, a change of protein input can influence performance by changing overall plane of nutrition. To a large extent this results from changes of digestibility and associated intake of ration ingredients. Within this context it appears that at high levels of feeding rumen microbial demand for nitrogen per unit fermentable organic matter is high; initial failure to meet this need for nitrogen probably accounts for many responses to protein supplementation in practice through stimulation of ruminal digestion. Second is that changing "protein" supply to tissues can alter the pattern and efficiency of absorbed nutrient use. In early lactation protein supplementation favors partition of available nutrients toward mammary secretion. There are effects on glucose and fatty acid metabolism, all interacting with the endocrine system within a metabolic framework that tends to conserve those nutrients (amino acids, glucose) that are in shortest supply relative to demand. Response to increased input of amino acids depends both on physiological state of the cow and balance of all nutrients absorbed from the gastrointestinal tract.

This article has been cited by other articles:

				A. J. Heinrichs, S. M. Emanuele, and C. M. Jones Altering Protein and Sugar in Postpubertal Dairy Heifer Diets Professional Animal Scientist, June 1, 2008; 24(3): 219 - 223. [Abstract] [PDF]

				A. Rotger, A. Ferret, S. Calsamiglia, and X. Manteca Effects of nonstructural carbohydrates and protein sources on intake, apparent total tract digestibility, and ruminal metabolism in vivo and in vitro with high-concentrate beef cattle diets J Anim Sci, May 1, 2006; 84(5): 1188 - 1196. [Abstract] [Full Text] [PDF]