Intestine: IL-6 (at week 4) ↑Kidney: IL-6 (at week 2) ↑,IL-8 (at week 4) ↑,IFN-γ (at week 4) ↑,g-lysozyme (at week 4) ↑Phagocytic activity (at week 2) ↑,NBT reaction (respiratory burst, at week 4) ↑,Natural infection of S. parauberis ↓. This evidence concerns the gene IL6 and infection.