THE EFFECTS OF SOCIAL HOUSING CHANGES, TEMPERAMENT AND SOCIAL RANK ON THE MICROBIOME COMPOSITION AND DIARRHEA RATES IN A COLONY OF MAURITIUS-ORIGIN MACACA FASCICULARIS

The gut-brain axis has been implicated in health outcomes related to physical and mental health in humans and animals. Social housing changes can be a source of stress in laboratory animals, and this stress may cause a negative shift in the gut flora (“gut dysbiosis”) that can play a role in diarrhea. Diarrhea is the most common health problem noted in captive macaque populations, and it can have significant consequences. This study characterized changes in the microbiome of primates (Macaca fascicularis) that experienced a change in social housing and were exhibiting diarrhea. As an adjunct, behavior aspects (temperament and social status) and fecal cortisol (a measure of stress) levels were evaluated to see if there is correlation with presence and severity of diarrhea. Fecal samples of recently-imported animals were collected during specific routine sedation events. As the animals experienced a housing change, the entire cohort was monitored for diarrhea. Matched-case samples (one sick, one healthy animal) were collected when the diarrhea outbreaks began. Samples from each time point per animal were evaluated via NexGen 16S microbiome analysis and cortisol levels. No significant correlation was determined between temperament test results/social rank, HPA axis activity and diarrhea. Significant changes in alpha and beta diversity and in abundance levels of several taxa were noted on the microbiome analysis between the two time points and animals with and without diarrhea. Characterization of these changes will direct future interventions.