The Impact of Altered Diet Presentation on Time Budget of Research Housed Rhesus Macaques (Macaca Mulatta)

Rhesus macaques in the wild are known to adapt to a changing environment spanning different types of geography in order to find and process a wide variety of dietary resources. Captive rhesus are not faced with the same challenges when it comes to accessing dietary resources to meet their daily caloric need. Standard diet presentation for research-housed rhesus macaques involves placement of the nutritionally complete diet in an open feeder hung on the front portion of the enclosure. The goal of this project was to place a modified diet feeder on the top of the enclosure of thirteen rack-housed rhesus to increase the effort and time required to obtain the daily ration. The data demonstrated a statistically significant increase in upright posture (p<0.05) and appetitive behaviors (p<0.001) indicating an increase in time and effort to obtain daily ration. However, no significant impact on performance of maladaptive behavior was observed. Future evaluation with larger cohorts of primates is warranted in order to determine the impact of covariates (such as age, sex, social housing, and study type), and incorporate additional measures of welfare to better predict impact on individual primate welfare.