In the early stages of infection (at 1 dpi), the administration of the essential oils-based phytobiotic Intebio into the diet of growing chickens could contribute to enhancing the immune response induced by Salmonella infection via upregulation of AvBD10, IL6, IL8L2, CASP6 and IRF7. Subsequently (at 23 dpi), a lowered expression of AvBD11, IL6, IL8L2, CASP6 and IRF7 occurred in birds fed Intebio suggesting an earlier suppression of the inflammatory reaction. The gene discussed is IRF7; the disease is infection.