COLIFORMS AND ENTEROCOCCI ISOLATED FROM THE INTESTINAL-TRACT OF CONVENTIONAL MICE

Coliforms and enterococci were isolated from the intestinal tract of infant (12-day-old) and adult (6-to 8-week-old) conventional mice. Eighty coliform isolates and eighty enterococcal strains were grouped according to their ability to ferment or hydrolyze various substrates. Sixty-one of the coliform isolates were identified as Escherichia coli. The remaining 19 strains were similar to E. coli, but did not produce β-galactosidase. The enterococci belonged to two species:Streptococcus faecium and S. faecalis. Four biotypes of S. faecium and two biotypes of S. faecalis were detected. Xylosefermenting enterococci were isolated with a higher frequency from infant mice than from adults. © 1979 Springer-Verlag New York Inc.