Abstract
The selection efficiencies of 6 media for examining microflora of mice were investigated with the organisms isolated from the feces and cecal contents of conventional mice By means of morphological and biochemical tests, of 260 isolates from all types of colonies on DHL agar plates, 254 (97.7%) were identified as Enterobacteriaceae. Also 244 (93.8%) of 260 from typical colonies on SF agar, 153 (85.0%) of 180 from typical colonies on mannitol-salt agar, and 176 (97.8%) of 180 from all colonies on LBS agar, 240 (92.3/) of 260 from all colonies on NBGT-blood agar, and 148 (82.2%) of 180 from typical colonies on potato-dextrose agar were identified as Streptococcus, Staphylococus, Lactobacillus, Bacteroides and yeast, respactively. These results appear to indicate that the organisms of various groups can be distinguished routinely by their colony appearance on the selective media. The constitution of genera and species of organisms may differ even among mice born to the same mother and reared in a same cage, and it was shown to be changeable also in the same animal with different ages as well as different parts of the digestive tract.
