Diversity of spp. circulating in a rhesus macaque () breeding colony using culture and molecular methods.

Unlabelled: and represent the leading causes of bacterial gastroenteritis in humans, and infections can produce post-infectious irritable bowel syndrome (PI-IBS). Rhesus macaques () (RM) are similarly susceptible to acute campylobacteriosis and represent a potential model of PI-IBS. We characterized the species circulating in an RM breeding colony using culture, qPCR, and whole genome sequencing (WGS). We also compared the and prevalence in RM as detected with qPCR versus culture and identified risk factors for bacteria presence and intestinal disease. Culture of 275 samples yielded (103) and (8), of which 21.6% were resistant to quinolones and 3.6% were resistant to macrolides. Multidrug-resistant isolates were obtained exclusively from animals exhibiting diarrhea or with histologically confirmed chronic enterocolitis. WGS revealed a non-clonal population of spp. Genotypic predictions of resistance were excellent except for aminoglycosides. All sequenced isolates contained genes for all subunits of cytolethal distending toxin. qPCR detected a prevalence of 45.9% for and 29.6% for . The quantity of either bacteria was significantly higher ( < 0.05) in animals with intestinal disease compared to healthy animals, though only young age was significantly associated with the presence of sp. or intestinal disease. Significantly more positive animals were detected with qPCR than with culture. These results provide a comprehensive characterization of spp. circulating in a breeding colony of RM in the United States and suggest that qPCR is superior for the detection of in RM.

Importance: Gastrointestinal disease is one of the most common reasons for hospitalization in non-human primate colonies and accounts for over one-third of non-research related euthanasia. In rhesus macaques, this manifests as both acute diarrhea and chronic enterocolitis (CE), a syndrome of chronic diarrhea resulting in poor weight gain or weight loss which is minimally responsive to treatment. spp. are major causes of acute enterocolitis in rhesus macaques and may predispose individuals to the development of CE, similar to post-infectious irritable bowel syndrome in humans. Despite these concerns, there are few studies characterizing in rhesus macaque colonies, in particular utilizing whole genome sequencing and assessing findings with respect to the health status of the host. Our findings provide insight into strains circulating in rhesus macaque colonies, which can improve clinical monitoring, assist in treatment decisions, and provide new avenues of investigation into campylobacteriosis as a catalyst for CE.