[Abstract Title]. - Society for Neuroscience

approximately 1.2 times higher than fat mass measurements using CCA, while QMR lean mass
measurements are approximately 0.86 times those obtained using CCA. The consistent linear
correlations between measurement methods indicate that studies using either method can be
directly compared. This study also demonstrates that QMR measurements have higher precision
for both fat and lean mass than measurements obtained using CCA. The coefficient of variation
(CoV) from repeated measures was used to estimate precision of methods. In both fat and lean
mass measurements, QMR showed significantly less variation between measurements than did
CCA analysis (Fat mass: QMR Live = 0.942 ± 0.122; CCA = 5.286 ± 1.457; p = 0.0095; Lean
mass: QMR Live = 0.225 ± 0.030; CCA = 0.975 ± 0.182; p = 0.0010). No significant differences
in fat or lean mass CoV by strain were observed. We conclude that QMR offers a fast, nonterminal,
and accurate method of body composition analysis, yielding measurements comparable
to that obtained by CCA without the need for time-consuming chemical analyses of the latter
method. This study and previous investigations using mice demonstrate that the EchoMRI QMR
system is a valid method for body composition analysis in obesity research.
Disclosures: J.P. Nixon, None; M. Zhang, None; C.M. Novak, None; J.A. Levine, None; C.
Kotz, None.
Poster
284. Regulation of Food Intake and Body Weight: Integration of Peripheral Signals:
Systems
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 284.10/QQ5
Topic: E.07.b. Integration of peripheral signals: Systems
Support: Unrestricted gift from Vivilac, Inc, Ashton, MD
Title: Growth and body composition of Charles River Sprague-Dawley rats
Authors: J. LEGER 1 , *R. R. SAKAI 2 , T. CASTONGUAY 1 ;
1 Nutr. and Food Sci., Univ. of Maryland, College Park, MD; 2 Dept Psych, North, Univ.
Cincinnati GRI, Cincinnati, OH
Abstract: Laboratory rats have been used for studying the interaction between diet and body
composition for more than 100 years. One of the assumptions that an experimenter makes in
using rats is that if animals are fed the same diet and housed in the same environment that their
growth and body composition will be the same. Differences in growth and body composition
have been associated with strain, sex, cage size, activity level and a host of other environmental
conditions (temperature, humidity, light cycle etc.). During the past year, we had the opportunity