Effet du régime alimentaire sur l'équilibre entre 14 souches microbiennes ensemencées dans le tube digestif de souris axéniques adultes et sur l'établissement de ces souches chez leurs descendants entre la naissance et le sevrage

Abstract

Ten strictly anaerobic bacterial strains belonging to the genera Inflabilis (I), Zymobacterium (Z), Acuformis (A), Streptococcus (S1, S2), Ristella (R), Clostridium (C), Eubacterium (E), Pasteurella (P), and Veillonella (V); three facultatively anaerobic strains belonging to the genera Actinobacillus (Ac), Lactobacillus (L), and Staphylococcus (St); and one yeast strain of the genus Torulopsis (T) were inoculated into adult male and female axenic mice fed either a commercial diet A or a semisynthetic diet B.Three strains (I, Z, St) did not establish in any "gnotoxenic" animals. One strain established only in animals fed diet B (S2). The average number of each of the other 10 strains is 10 to 100 times less in animals receiving diet B than in those given diet A. The microflora of the stomach and the small intestine is more variable and less abundant in mice fed diet B than in those receiving diet A. For strains A and C there is a net decrease in colon populations as related to those of the caecum or the feces, especially in mice receiving diet B.In the digestive tract of young "gnotoxenic" mice sacrificed before weaning, the facultatively anaerobic microflora is always established before the strictly anaerobic flora but does not change the establishment of the latter. Finally, the diet of the mother affects appreciably the establishment kinetics of strains L, St, and T in the young mice.