Efficacy of 3 types of foraging enrichment for rhesus macaques (Macaca mulatta)

J Am Assoc Lab Anim Sci. 2011 Nov;50(6):888-94.

Abstract

Primate facilities provide environmental enrichment to improve animal wellbeing, increase opportunities for expression of species-typical behaviors, and decrease the occurrence of stereotypic behaviors. The current study assessed the efficacy of 3 types of foraging enrichment: puzzle balls, supertubes, and shakers. We assigned 48 rhesus macaques to 3 experimental groups, each of which received (after a 3-wk baseline observation period) 1 of the 3 enrichment devices intermittently for 3 wk. Observations were collected during 10-min sessions by using 1-0 sampling with 15-s intervals (480 h total). Observations were collected at the same 10 specified time points each week during the baseline period and after enrichment. Data were analyzed by using generalized linear mixed-effects modeling under the assumption that the underlying response followed a Poisson distribution. Foraging behavior increased significantly in all 3 groups and remained increased in some groups when enrichment was removed after 43 h. The 3 enrichment devices had different effects on individual expression of stereotypy: supertubes decreased it, shakers increased it, and puzzle balls led to a decrease followed by an increase. We present potential reasons for the changes in stereotypy and postulate a likely balance between the beneficial and negative effects of enrichment in any given environment.

Publication types

  • Comparative Study
  • Evaluation Study

MeSH terms

  • Animals
  • Appetitive Behavior / physiology*
  • Feeding Behavior / physiology*
  • Female
  • Housing, Animal / standards*
  • Linear Models
  • Macaca mulatta / physiology
  • Macaca mulatta / psychology*
  • Male
  • Stereotyped Behavior / physiology*
  • Time Factors