The Pig as a Model for the Study of Obesity and of Control of Food Intake: A Review

The use of the pig for studies of food intake and obesity is reviewed. Effects of ambient temperature and taste on food intake as well as satiety factors impicating both neural and hormonal mechanisms originating in the gastrointestinal tract are considered; the integration of information in the central nervous system for both internal and external sources is hypothesized. Special concerns of food intake controls in the neonate are discussed, including effects of neonate sweet preference on food intake, gastrointestinal satiety factors, and hypoglycemia as a stimulus for food ingestion.For obesity studies, pigs offer several advantages, including their general physiological similarity to humans, similar fat cell size, and body fat distribution. Lipogenesis, lipolysis, and lipid mobilization are under intensive study in swine and the information obtained may have important application in studies of human obesity. The voluminous literature on metabolic differences between genetically lean versus obese populations of pigs suggests possibilities for application in humans. Greater characterization of differences and similarities between pigs and humans in important metabolic parameters related to regulation of food intake and obesity should facilitate better understanding and control of human obesity.