Exploring the Utility of the Gut Microbiome as a Longitudinal Health Monitoring Tool in Sanctuary Chimpanzees (<i>Pan troglodytes</i>)

The primary goal of captive primate management is to ensure optimal health and welfare of the animals in our care. Given that the gut microbiome interacts closely with host metabolism, immunity, and even cognition, it represents a potentially powerful tool for identifying subtle changes in health status across a range of body systems simultaneously. However, thus far, it has not been widely tested or implemented as a monitoring tool. In this study, we used longitudinal microbiome sampling of newly arrived chimpanzees at Chimp Haven to explore the feasibility of using the gut microbiome as a health and welfare biomarker in a sanctuary environment. We also tested the hypothesis that a transition to a new living environment, and integration into new social groupings, would result in temporal changes in chimpanzee gut microbiome composition. The collection of longitudinal microbiome data at Chimp Haven was feasible, and it revealed temporal shifts that were unique to each individual and, in some cases, correlated to other known impacts on health and behavior. We found limited evidence for microbial change over time after arrival at Chimp Haven that was consistent across individuals. In contrast, social group and enclosure, and to a lesser extent, age and sex, were associated with differences in gut microbiome composition. Microbiome composition was also associated with overall health status categories. However, many of the effects we detected were most apparent when using longitudinal data, as opposed to single time point samples. Additionally, we found important effects of technical factors, specifically outdoor temperature and time to collection, on our data. Overall, we demonstrate that the gut microbiome has the potential to be effectively deployed as a tool for health and environmental monitoring in a population of sanctuary chimpanzees, but the design must be carefully considered. We encourage other institutions to apply these approaches and integrate health and physiology data to build on the utility of gut microbiome analysis for ensuring the welfare of captive primates in a range of contexts.