[Kinetics of setting up of a human fecal flora in germ free mice and trial of decontamination of antibiotherapy (author's transl)].

We have tried in this study to reproduce in germfree mice a bacterial equilibrium observed previously in the gastrointestinal tract of child "L.N.", reared in a plastic isolator. Eight bacterial strains were studied. Seven had been fortuitously introduced: Acinetobacter lwoffi LN1, Staphylococcus epidermidis LN2, Clostridium perfringens LN3, Plectridium anatum LN4, Streptococcus bovis LN5, Enterobacter cloacae LN6, Corynebacterium sp LN7. The eighth strain was purposely administered to the child in order to take advantage of an antagonism between this strain and spontaneously acquired flora. This strain is Bacillus licheniformis FD1. The gnotoxenic mice proved to be a good experimental model because we found their bacterial equilibrium comparable to that observed in child L.N. In addition, we studied the decontamination procedures of the gastrointestinal tract of mice by observing both the antagonism of B. licheniformis with bacitracin, and the action of a suitable mixture of antibiotics. Conditions for the realization of this decontamination are discussed in this study.