"prebiotics in Infant Nutrition"

The development of the intestinal flora in newborn infants starts during birth when the aseptic gastrointestinal tract of the fetus is inoculated by bacteria from the mother’s intestinal and vaginal flora. This leads to a diverse flora comprising Bifidobacteria, Clostridia, and gram positive Cocci (Heine et al., 1998). After this first inoculation, the flora changes rapidly, presumably under the influence of the diet. In entirely breast-fed infants the flora is predominately Bifidobacteria whereas in formula-fed infants the flora is more diverse (Harmsen et al., 2000; Figure 1). The introduction of solid food leads to the disappearance of the predominance of Bifidobacteria in breast-fed infants and at 12 months of age the flora starts to resemble that of adults in number and composition (Stark and Lee, 1982).