Behavior, appetite, and urinary cortisol responses by adult female pigtailedmacaques to cage size, cage level, room change, and ketamine sedation (2000)

Crockett, C. M., Shimoji, M., Bowden, D. M.

Abstract

Eight female pig-tailed macaques were tested, 4 in upper-row and 4 in lower-row, barren cages. Cage size was not significantly related to abnormal behavior [ included stereotypical locomotion, hair-plucking and odd gestures such as saluting ] and cortisol excretion. Ketamine injection produced an increase in cortisol. Cage changes were associated with minimal cortisol elevation and appetite suppression. No differences in stress parameters related to cage level were detected.. Pigtailed macaques strongly resembled longtailed macaques except they showed weaker responses to the new room and cage change, probably because the pigtails had spent more time in captivity. These findings support the conclusion that increasing cage size to the next regulation size category would not have measurable positive effects on the psychological well-being of two species of laboratory macaques. ... The primary purpose of these studies was to investigate the influence of cage size on behavioral and hormonal measures of stress and well-being. Our findings with pigtailed macaques are consistent with those of our previous research with longtailed macaques. ... We do concur with the view that cage size, within the wide range addressed by USDA regulations .. is one of the least important in the promotion of psychological well-being in primates. ... Replacement of cages simply to achieve minor increases in cage size is a waste of resources.