Local and systemic levels of IL-8, TNF-α, and IL-10 in the gnotobiotic piglets. The levels of IL-8 (A,D,G), TNF-α (B,E,H), and IL-10 (C,F,I)) in the ileum (A–C), colon (D–F), and plasma (G–I) in the germ-free piglets (GF) and the piglets colonized/infected with L. amylovorus (LA and LA+ST), L. mucosae (LM and LM+ST), E. coli Nissle 1917 (EcN and EcN+ST), and S. Typhimurium (ST, LA+ST, LM+ST, and EcN+ST) are depicted. Kruskal–Wallis test with Dunn’s multiple comparison post-hoc test was used to compare differences among the groups. The cytokine levels were measured in six piglets per group. The values are presented as median and range. Statistical differences P < 0.05 are denoted with different letters above the columns and the same letter shown above the column indicates no statistically significant differences.