[Alteration of the normal intestinal flora in human sucklings within the last 20 years]

Analyses of the feces-flora and the feces-pH of breastfed infants and of infants nourished with commercial formulae (Ki-Na, Milasan) performed since 20 years were evaluated. In both regimens decreasing numbers of Bifidobacteria could be remarked. The dominating position of this groups of bacteria was limited more and more. Since 1971 the Bifidobacterium biotype, characteristic of feces of breastfed infants could be proved no more. Simultaneously germs of the E. coli-group and neonmycine-resistent forms increased. With breast-milk Proteus distinctly increased in the feces, whereas, formulae on cow's milk basis caused the reversed effect. Bacteroides and the group of H2S producing bacteria remained unaltered. In the stools of breastfed infants the pH-value increased slowly. These tendencies were marked still stronger in prematures. Enhancing influences from the environment as possible reasons for these developments were discussed.