Maintenance requirement and energetic efficiency of lean and obese Zucker rats
Deb, S.; Martin, R.J.; Hershberger, T.V.
Journal of Nutrition 106(2): 191-197
1976
ISSN/ISBN: 0022-3166 PMID: 1249645 Document Number: 106200
The maintenance requirement and the energetic efficiency of male lean and obese Zucker rats 6 weeks old were estimated by the body balance method. The lean and obese rats were in 3 groups of 5 and for 4 weeks were fed to appetite or given 75 or 50% of free intake. The obese rats ate more food and gained significantly more weight than the lean rats. Obese rats used dietary energy more efficiently and protein less efficiently than the lean rats. The efficiency with which obese rats used metabolizable energy for gain was 36%, compared with 15% for the lean rats fed freely. The calculated values for the efficiency of utilization of metabolizable energy (ME) above maintenance for obese and lean were 51.4 and 21.4%. The maintenance ME requirement on the basis of metabolic body size for the obese and lean was 122 and 130.5 kcal/kg0.75 daily for the 4-week period. The findings indicated that energetic efficiency was higher in obese than in lean Zucker rats and suggested that the higher energetic efficiency was not the result of a significantly lower maintenance requirement.