Development of Obesity: Mechanisms and Physiology.

Normal adult animals living in nonstressful environments that receive nutritionally sound diets balance their energy expenditure with their energy intake over the long-term. Most knowledge of mechanisms underlying the precise balance of energy is derived from research on rodent models and human correlates. This knowledge is believed applicable and pertinent for understanding causes of obesity in dogs and cats. The roles of satiation and adiposity feedback, cognitive input, energy expenditure, and physical activity are reviewed. Dietary and environmental factors especially relevant to promotion of overweight body condition are reviewed. These include dietary fat and palatability, inactive and stressful lifestyle, and obesogenic effects of neutering.