Figure 4

Recoveries of nalidixic acid-resistant E. coli from internal organs after homologous re-challenge. APEC-primed turkeys (n = 10) and their age-matched controls (n = 10) were challenged with 10⁷ CFU of APEC strain χ 7122nal^R via the intra-airsac route and sampled after 24 h. The data represent the mean log₁₀CFU/g tissue ± standard error of the mean.* = P ≤ 0.05; ** = P ≤ 0.01; *** = P ≤ 0.001.