FIG. 7.

Colonization of the intestinal tract of chicks with a coculture of strains BEN2908 and BEN2908 Δfrz::kan. Six 12-day-old axenic White Leghorn chicks were fed a coculture of strains BEN2908 and BEN2908 Δfrz::kan. The proportion of the mutant in feces of the chicks was analyzed during 7 days. The proportion of the mutant in the inoculum was 51% (dotted line). Results are presented as means ± standard deviations for the six animals analyzed. The significance of the difference between the proportion of the mutant in the inoculum and in chick feces was tested with the Student t test (*, 0.01 > P > 0.001; **, P < 0.001).