An experimental model to reproduce some bacterial intestinal cocultures in germ-free mice

The objective of this study was to create a stable experimental model to act as a living incubator for the main important intestinal bacteria. We have therefore inoculated germ-free mice with the most important bacteria of the human intestinal microflora, in order to study the effect of some oral antibiotics on the intestinal microflora. Sixty germ-free mice, 7 weeks old and of either sex, were inoculated orally with human faecal bacteria by means of their drinking water. Administrations were made at regular intervals following a scheme that respected some of the metabolic inter-relationships of the microorganisms used. The results showed that colonization of the germ-free mouse intestines had been achieved by most of the bacteria that had been inoculated. This "coculture" was stable in time, contrary to what happens when in-toto lyophilized faeces are administered, and the bacterial concentrations for each strains were similar to those found in human faeces.