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 Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hix, V. M. Articles by Glacoletto, L. J. Search for Related Content PubMed Articles by Hix, V. M. Articles by Glacoletto, L. J.

Determination of Specific Gravity of Live Hogs by Suppressed Zero Techniques¹

Michigan State University, East Lansing^{,6, 7,}

Abstract

The conventional apparatus used earlier in this laboratory (Gnaedinger et al., 1963b; Hix et al., 1964) for measuring body volume was modified by the addition of two chambers, identical to those in use. The addition of these chambers resulted in the formation of a suppressed zero measuring system in which the relatively small difference in volume between the subject and an inert reference was determined, rather than the total volume of the subject.

The specific gravity of 24 hogs was determined and the values were compared with chemical analysis data. Specific gravity values determined by helium dilution were significantly correlated (r=0.59) with those obtained by air displacement. However, specific gravity values determined by both methods were not significantly correlated with chemical composition, except for percent ash. The major source of error involved in both the air displacement and helium dilution procedures was due to differences in relative humidity between the subject and reference chambers and to changes in relative humidity within the subject chamber.

Chemical analysis showed the average composition of the 24 hogs to be 52.00% moisture, 30.36% ether extract, 15.21% protein and 2.57% ash. A highly significant correlation of –.98 was obtained between percent total moisture and percent total ether extract and a regression equation was computed for predicting total fat from total body water. Of the various body compartments, the chemical composition of the shoulder and ham was most closely related to composition of the whole animal. Equations were computed for predicting the chemical composition of the whole animal from the percent composition of the shoulder. However, the standard errors of the estimate showed that this prediction would not be too useful.

¹ Journal Article 3875, Michigan Agricultural Experiment Station, East Lansing.

² Present address: The Quaker Oats Co.,617 West Main St., Barrington, 111.

³ Department of Food Science.

⁴ Department of Physiology.

⁵ Department of Electrical Engineering.

⁶ The data reported herein are a portion of a thesis submitted to the School of Advanced Graduate Studies, Michigan State University, by the senior author in partial fulfillment of the requirements for the Ph.D. degree.

⁷ This study was supported in part by a grant-in-aid from the Nutrition Foundation, Inc., 99 Park Ave., N. Y., N. Y.