Pair-housing macaques with biomedical implants: a safe and practical alternative to single-housing (2004)

Roberts, S. J., Platt, M. L.

Abstract

Recognition of the importance of social interaction for primate well-being has led to new USDA guidelines recommending that animal facilities provide social enrichment for captive primates, as long as doing so does not endanger the animals or interfere with research goals. Group- or pair-housing is the best way to provide social enrichment, but many primates used in medical research are housed singly because they have implants which may make them more vulnerable to inflicted injury. In addition, pairing adult male monkeys is often considered too difficult and too impractical to attempt. The goal of this study was to evaluate these assumptions. Eight adult male rhesus macaques (Macaca mulatta) and two adult male crab-eating macaques (Macaca fascicularis) were evaluated for pairing and then housed with a compatible partner for up to three years. During the period of study, 9 of the 10 monkeys received cranial and scleral search coil implants. On average, each monkey was compatible with 69% of partners, and this high degree of compatibility allowed monkeys to be paired continuously within three weeks of initial evaluation. Moreover, the rate of implant failure during pair-housing (0.07 failures per month) was not significantly different from the rate of implant failure when monkeys were singly-housed (0.098). These data demonstrate that pair-housing provides a safe and practical social alternative to single-housing for adult male macaques with biomedical implants.