Distribution and Seasonal Fluctuation of Bacteria Isolated from Mice and Rats

Bacterial pathogens can affect the experiment data by causing side immune responses. This study aimed to survey the status of laboratory animal quality for major suppliers and research institutes on a national scale, and also the distribution of respiratory and intestinal organ by the turning of the season. We monitored each organ from 738 mice and rats which are being distributed by 34 major institutes in Korea, taken 1,616 isolates including 857 (94.90%) and 759 isolates (97.31%), respectively, with VITEK and 16S rRNA sequence. The 945 (56.15%) and 671 (39.87%) of 1,616 isolates exhibited in respiratory organs and intestinal organs, respectively. Aerococcus viridans, Aeromonas salmonicida, Dermacoccus nishinomiyaensis, Kocuria rosia, Leucomostoc pseudomesenteroides, Micrococcus luteus, Sphingomonas paucimobilis, Staphylococcus lentus, Staphylococcus xylosus and Streptococcus parasanguinis were especially isolated in only respiratory organ. The microbial flora which belong to same species and genuses also distributed higher in autumn than in spring. Proteus vulgaris showed mainly in spring, while Sphigomonas paucimobilis, Micrococcus luteus, Leclercia adecarboxylate, and Kocuria rosea in autumn. Paenibacillus polymyxa, Granulicatella elegans, Granulicatella adiacens, Enterobacter cloacae, Brevibacillus choshinensis, Bacillus firmus, Bacillus circulans, Acinetobacter baumannii, Acromobacter denitrificans were specifically distributed in spring, and Streptococcus pneumoniae, Sphingomonas thalpophilum, Pasteurella canis, Micrococcus lylae, Brucella meltensis and Salmonella genus showd in autumn. These result suggested that composition and seasonal fluctuation of bacteria will serve as basic information for the improvement of domestic laboratory animal quality.