Mice were infected (intraperitoneally) IP or orally (as noted) with a 50:50 mix of the indicated strains. Competition assays were performed in streptomycin-treated (+Strep) or untreated (−Strep) mice (see Experimental procedures). Bacteria were recovered from the spleen (designated SP) in the case of IP competition assays or from the spleen (SP), small intestine (SI), and large intestine (LI) in oral competitions. The competitive index (CI) was calculated as described in experimental procedures and is shown for each mouse. The line indicates the geometric mean for each set. The Student t test was used to compare the CIs to the inocula or between groups. p=<0.05 (*), p=<0.005 (**), p=<0.0005 (***). The strains used were JS749, JS2125, JS2164, JS2160, JS2162, JS2075.