Effects of Pair Housing on Behavior, Cortisol, and Clinical Outcomes During Quarantine-Like Procedures for Rhesus Macaques

The study evaluated the impact of pair housing on 40 adolescent male rhesus macaques following an intrafacility transfer, a situation analogous to quarantine. The researchers compared behavior, fecal cortisol levels, body weight, and diarrhea occurrence between single- and pair-housed macaques. Additionally, they retrospectively analyzed body weight and diarrhea occurrence in another 120 macaques who underwent a similar transfer. The results showed that pair-housed macaques engaged in fewer undesirable behaviors, such as self-clasping, and had a lower incidence of diarrhea compared to single-housed individuals. However, there were no significant differences in cortisol levels or alopecia between the two groups. The findings suggest that pair housing can improve welfare by reducing stress-related behaviors and health issues during post-transfer adjustment periods.