Trauma rates and patterns in specific pathogen free (SPF) rhesus macaque (Macaca mulatta) groups

There are some predictable patterns of trauma in captive rhesus macaque (Macaca mulatta) social groups. Several factors have been documented to contribute to these patterns, including group formation of unrelated animals, and the establishment of dominance ranks. Here, we report on how socially induced trauma in groups of rhesus monkeys is influenced by the breeding season, numbers of matrilines per group and matriline size. We analyzed 3 years of data collected from veterinary admittance logs for four groups in our specific pathogen free (SPF) breeding colony. Since the groups differed in time from formation, both the numbers of matrilines and the composition of those matrilines were different. Across the four groups, trauma rates were significantly higher during the fall breeding season than the spring and summer months when births occur. The group that was formed most recently, comprised of the greatest number of matrilines but fewest related animals, showed significantly higher rates of trauma than the older social groups. Further, the middle and lowest ranking families received signifincantly higher rates of trauma than the highest ranking families, suggesting a rank–related phenomenon. Additionally, there was a significant negative correlation between numbers of adult females in a matriline and rates of trauma observed in each matriline, but the numbers of adult females are significantly higher in the top ranked families compared to all of the other matrilines. These ...
Source: American Journal of Primatology - Category: Psychiatry & Psychology Authors: Tags: RESEARCH ARTICLE Source Type: research