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 Google Scholar Google Scholar Articles by Arnold, R. N. Articles by Trenkle, A. Search for Related Content PubMed PubMed Citation Articles by Arnold, R. N. Articles by Trenkle, A.

Evaluation of the Use of Deuterium Oxide Dilution Techniques for Determination of Body Composition of Beef Steers¹

Iowa State University², Ames 50011

Abstract

Body composition as estimated by a one- or two-compartment deuterium oxide dilution technique was compared with directly measured body composition of 15 large- and 15 small-frame steers. Body composition of the steers was measured at 219, 412 and 603 kg live weight. Empty body protein was overestimated (P<.05) 3.6% from a one-compartment model (1CM, using the slope, intercept method), while empty body protein was underestimated (P<.05) 5.4% from a two-compartment kinetic model (2CM). Empty body ether extract estimated by 1CM was not significantly different from the direct method, although 4.7% larger. Empty body ether extract was overestimated (P<.001) 32.2% by the 2CM. Empty body water was accurately estimated from the 1CM when a 3.2% correction factor was used for the overestimation of total body water by the 1CM, but water in gastrointestinal tract contents was overestimated (P<.001) 13.4% by the 1CM. Empty body water was underestimated (P<.001) 7.8% by the 2CM, and water in gastrointestinal tract contents was overestimated (P<.001) 41.8% by the 2CM due to its dependence on regression equations that differ between groups of cattle. The 2CM offered no advantage over the 1CM. A three-compartment model was not better than the 2CM in estimating body water compartments. Assuming the amount of empty body water associated with either empty body protein or ash to be constant seemed to be valid. Suggested values calculated from data presented in the literature for growing cattle with an empty body weight greater than 175 kg are .302 and .0668, respectively, for the ratios of protein and ash to water. The relationship between empty body fat and water was, percentage empty body fat = 94.27 – (1.267)(percentage empty body water), which had a 1.25 residual standard deviation and a .98 coefficient of determination.

¹ Journal Paper No. J-11556 of the Iowa Agr. and Home Econ. Exp. Sta., Ames. Project No. 2644. This study was supported in part by grants from the Iowa Corn Promotion Board and the Iowa Beef Industry Council.

² Dept. of Anim. Sci.