Bifidobacterium Gut Modulation in Mice

The transplantation experiment was carried out according to previous reports with modifications (27 (link), 28 (link)). Mice at 3 weeks of age were treated with a combination of metronidazole (1 g/L), neomycin sulfate (1 g/L), ampicillin (1 g/L), and vancomycin (0.5 g/L) (Sangon Biotech) for 2 weeks. Then, at 5 weeks of age, the water was replaced by antibiotic-free water and the mice were administered (i.g.) with a mixture of 2 × 10⁸ CFU Bifidobacterium longum (ATCC15697) and 2 × 10⁸ CFU Bifidobacterium adolescentis (ATCC15703). Also, the antibiotic-free drinking water was supplied with B. longum (final concentration ≈10⁶ CFU/mL) and B. adolescentis (final concentration ≈10⁶ CFU/mL). Mice in the control group were administered (i.g.) with an equal volume of Modified Reinforced Clostridial Medium (BD 218081) but without bacterial cells and the antibiotic-free drinking water was also supplied with an equal volume of Modified Reinforced Clostridial Medium. Mice were evaluated after 15 days.