Detection and treatment strategy for Tritrichomonas muris in the common laboratory mouse

Summary Maintaining a specific pathogen-free (SPF) mouse colony is critical to avoid potentially confounding variables introduced by unknown infections. Here, we report an instance of protozoan Tritrichomonas muris ( T. muris ) infection of mice within an SPF facility. Although T. muris has been considered a commensal organism, we observed instances of asymmetric infection in gene-knockout mice as compared to wild-type mice. We utilized treatment with metronidazole and confirmed successful elimination of T. muris from our SPF colony using extraction of fecal DNA followed by PCR detection. We propose that T. muris testing should be considered for SPF mice, particularly in immunity studies.