Figure 3.

Effect of Δspi2 mutation (deletion of SPI2 structural genes) in the colonization of chicken cecum (A) and spleen (B) by Typhimurium. Competitive indexes are from mixed oral infections in chickens with the wild type and the Δspi2 strains. Each point represents an organ from an individual bird at the indicated day following the infection. The table summarizes the number of animals sampled (n), the geometric mean of the competitive indexes (mean CI), and the P value from a two-tailed T-test.