Feeding behavior during experimentally induced obesity in monkeys

Area of Science:

• Primate research
• Obesity studies
• Nutritional science

Background:

• Understanding feeding behavior is crucial for obesity research.
• Investigating obesity induction and remission provides insights into metabolic regulation.

Purpose of the Study:

• To examine how induced obesity and subsequent weight loss affect feeding patterns in male rhesus monkeys.
• To determine the caloric requirements for maintaining elevated body weight post-obesity.

Main Methods:

• Male rhesus monkeys were made obese using sustained intragastric (IG) feeding of a liquid diet at escalating caloric levels.
• Oral intake and body weight were monitored during overfeeding and remission phases.
• Caloric intake needed to maintain peak body weight was assessed.

Main Results:

• Intragastric feeding led to rapid weight gain (at least 5x baseline) and suppressed oral intake.
• Following cessation of IG feeding, monkeys exhibited temporary food refusal, followed by gradual normalization of oral intake and weight loss.
• Fewer kilocalories per kilogram were required to maintain peak body weight compared to baseline intake.

Conclusions:

• Sustained intragastric feeding effectively induces obesity and alters feeding behavior in rhesus monkeys.
• Weight and feeding behaviors show a capacity for remission, though metabolic adaptations may persist.
• Maintaining elevated body weight requires fewer calories, suggesting altered metabolic efficiency post-obesity.