Food search demand effort effects on behavior and cortisol in adult female squirrel monkeys.
Laboratory-born, group-housed, ovariectomized adult female squirrel monkeys (Saimiri sciureus) were exposed to feeding conditions in which the availability and accessibility of food were altered. Both high- and variable-demand feeding conditions were utilized. The variable-demand condition required alternating periods of high effort (120% of normal daily intake presented) and low effort (600% of normal daily intake presented) to obtain food for 10-12 weeks. An additional group was exposed solely to the high-demand condition for 10 weeks. Blood samples were obtained weekly, and behavioral observations were conducted daily. In the variable-demand condition, plasma cortisol was elevated above baseline during the periods of high effort. For the constant high-demand group, cortisol was elevated for the duration of the experimental treatment. Contact with other animals, as well as a species-specific inactive posture, decreased as a result of exposure to high demand. Maintenance of body weight indicated that nutritional deprivation did not occur. The imposition of increased food-seeking efforts provides an ecologically relevant and noninvasive method of producing chronic stress in the squirrel monkey.
Champoux
M
M
Department of Psychiatry and Behavioral Sciences, Stanford University, CA 94305-5095.
Zanker
D
D
Levine
S
S
D000818:Animals; D001070:Appetitive Behavior / Q000502:physiology*; D001143:Arousal / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D006815:Hunger / Q000502:physiology*; D006854:Hydrocortisone / Q000097:blood*; D009042:Motivation; D012453:Saimiri; D012919:Social Behavior; D012931:Social Environment
D006854:Hydrocortisone