Table 5.

Fold changes of cytokine gene expression in the spleens of broilers after challenged with SE¹.

		Experimental treats
Gene	Age of post-ch2	NC	PC	EXP
IFN-γ	2 d	1.00 ± 0.35b	2.30 ± 0.19a	1.29 ± 0.12b
	6 d	0.39 ± 0.03b	1.31 ± 0.22a	0.38 ± 0.01b
IL-1β	2 d	0.99 ± 0.15	2.19 ± 0.36	1.17 ± 0.34
	6 d	0.63 ± 0.14b	1.64 ± 0.22a	0.32 ± 0.08b
IL-8	2 d	0.58 ± 0.22ab	1.81 ± 0.28a	0.30 ± 0.18b
	6 d	0.57 ± 0.09b	1.95 ± 0.24a	0.79 ± 0.12b
TNF-α	2 d	0.83 ± 0.11	0.80 ± 0.10	1.37 ± 0.49
	6 d	0.008 ± 0.0008	0.009 ± 0.001	0.007 ± 0.001

Mean ± SD in the same row with different superscript letters differ significantly (P < 0.05). ¹Each mean represents six birds. NC, birds fed a basal diet without challenged with SE; PC, birds fed a basal diet and challenged with SE; EXP, birds fed a basal diet with C. butyricum (10⁶ CFU/mL) and challenged with SE. ²The days after challenging.