Анотация: OBJECTIVE To determine effects of restriction feeding of a moderate-protein, high-fiber diet on loss of body weight (BW). voluntary physical activity, body composition, and fecal microbiota of overweight cats. ANIMALS 8 neutered male adult cats. PROCEDURES After BW maintenance for 4 weeks (week 0 = last week of baseline period), cats were fed to lose approximately 1.5 percent of BW/wk for 18 weeks. Food intake (daily). BW (twice per week), body condition score (weekly), body composition (every 4 weeks), serum biochemical analysis (weeks 0. 1.2. 4. 8, 12. and 16). physical activity (every 6 weeks), and fecal microbiota (weeks 0. 1.2.4.8. 12. and 16) were assessed. RESULTS BW. body condition score, serum triglyceride concentration, and body fat mass and percentage decreased significantly over time. Lean mass decreased significantly at weeks 12 and 16. Energy required to maintain BW was 14 percent less than National Research Council estimates for overweight cats and 16 percent more than resting energy requirement estimates. Energy required for weight loss was 11 PROCENT more. 6 PROCENT less, and 16 PROCENT less than American Animal Hospital Association recommendations for weight loss (80 PROCENT of resting energy requirement) at weeks I through 4, 5 through 8, and 9 through 18. respectively. Relauve abundance of Actinobacteria increased and Bacte-roidetes decreased with weight loss. CONCLUSIONS AND CLINICAL RELEVANCE Restricted feeding of a moderate-protein, high-fiber diet appeared to be a safe and effective means for weight loss in cats. Energy requirements for neutered cats may be overestimated and should be reconsidered.