SEPARATION AS A NEW ANIMAL-MODEL FOR SELF-INDUCED WEIGHT-LOSS

Animal models for weight loss are generally either stress mediated or following diet restriction (DR) schedules. We investigated weight loss in mice subjected to activity stress (ACT), DR schedules of 40, 60 an d 100% of daily requirements, and propose a new model for animal weigh t loss based upon separation. Mice were separated (SEP) from each othe r by perspex partitioning for 23 h per day, with free access to food f or one hour. No significant differences in weight loss were found betw een the ACT, SEP and 40 parts per thousand groups. However, mean food intake in the 40 parts per thousand group was half that of the ACT gro up (p < 0.001) and significantly less (p < 0.01) than the SEP group, w hich consumed amounts equivalent to 65 parts per thousand of daily req uirement. Separation of mice increases metabolic demands and may be us ed as a new, easily performed, animal model for weight loss. (C) 1997 Elsevier Science Inc.