飼育下の野生由来ハタネズミで検出されたFilobacterium rodentium

梶田亜矢子, 小久保年章, 目加田和之, 吉木 淳, 池 郁生

第71回日本実験動物学会総会

Filobacterium rodentium is a Gram-stain-negative filamentous bacterium that causes chronic respiratory infections in mice and rats. Filobacterium spp. has also been reported in rabbits, pigs, cattle, goats, wild deer, and cats. A recent report demonstrated that Filobacterium spp. colonized in water voles affected vole's population fluctuation through co-infection with other pathogens. Here, we describe the results of PCR, serology, and pathological examination of Filobacterium spp. in wild-derived rodents and shrews maintained under laboratory conditions. [Materials and methods] PCR targeted the 16S rRNA gene of F. rodentium. ELISA was carried out using enzyme-labeled Protein A and Protein G for detection. Pathological examination used H&E staining and silver staining. [Results and Discussion] F. rodentium PCR results of tracheal swabs from nine wild-derived animals (including five species of voles) were positive only for Microtus guentheri (Günther's vole). We designed primers to amplify the V2 to V7 region of the F. rodentium 16S rRNA gene and read the sequence (1,055 b), which was 100% identical to the sequence of the F. rodentium SMR-C T . ELISA of ten M. guentheri serum samples all showed higher absorbance than the positive control. Pathological examination revealed colonies of silver-stained rods on the respiratory ciliated epithelium, surrounded by clusters of inflammatory cells. These results indicate that F. rodentium infected M. guentheri, which will be the first report of natural