The designed and validated
assays were used to determine the amounts of different Lactobacillus species in fecal samples of infants
receiving a standard formula (SF) or a standard formula supplemented with galacto- and fructo-oligosaccharides
in a 9:1 ratio (OSF). A breast-fed group (BF) was studied in parallel as a reference. During the 6-week
intervention period a significant increase was shown in total percentage of fecal lactobacilli in the BF group
(0.8% 0.3% versus 4.1% 1.5%) and the OSF group (0.8% 0.3% versus 4.4% 1.4%)