FIGURE 3.

Antimicrobial activity of the animals’ intestinal fluids. S. aureus (A) and S. Typhimurium (B) (10⁹ CFU/ml) were incubated for 2 h at 37°C, in the presence of the intestinal fluids of 42 days mice fed with conventional diet, L. casei CRL 431 or L. paracasei CNCM-I 1518, for 7 and 5 days, respectively. After the co-incubation, viable bacteria were determined by plate count agar. A set of serial dilutions has been made and samples of each appropriate dilution were spread on top of solidified agar petri plates. Results are expressed as CFU/ml. Results (mean ± SEM) are representative of three independent experiments. Results were expressed as the differences in the CFU/ml before and after the incubation of the bacteria with the intestinal fluids. The statistics differences were calculated with respect to the control group that received conventional diet ^∗p < 0.05, ^∗∗p < 0.01.