Spontaneous obesity in maturing squirrel monkeys fed semipurified diets.
The squirrel monkey is usually a lean primate (5-10% fat) until the onset of the pubertal growth spurt at about 3 yr of age.  This characteristic is generally maintained thereafter for animals fed commercial monkey biscuits. Animals fed semipurified diets containing a moderate amount of fat and sucrose continue to gain weight, however, until a frank obesity is developed. Conventionally, an animal is labeled obese when the body weight is greater than 1,200 and 800 g for males and females, respectively. By 6 yr of age, practically 100% of the animals satisfy these criteria. The carcass composition from a subset of obese animals showed that fat content ranged from 18 to 40%, and that weight gain in males heavier than 800 g represents increasing proportions of fat. The annual weight cycling ascribed to sexual activity appeared to remain superimposed on the "basal" obesity. Food intake monitoring showed a significant hyperphagia associated with rapid weight gain. A major interaction between the neuroendocrine setting and a very palatable diet in the development of this syndrome is implied.
D000375:Aging; D000818:Animals; D001823:Body Composition; D001835:Body Weight; D004032:Diet; D002149:Energy Intake; D005260:Female; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D012453:Saimiri; D012737:Sex Factors