Table 10.

Effects of different levels of capsaicin on the immune organ indexes of broilers (g/kg).

Item	Control	Dietary capsaicin level (mg/kg)			SEM	P -value
		2	4	6		ANOVA	Linear	Quadratic
21 d
Spleen weight/BW	0.84	0.87	0.91	0.86	0.035	0.915	0.754	0.583
Thymus weight/BW	4.33	4.40	4.74	3.82	0.151	0.197	0.368	0.102
Bursa of Fabricius weight/BW	1.92ab	2.40a	2.05ab	1.82b	0.080	0.049	0.325	0.024
42 d
Spleen weight/BW	0.96	0.96	0.97	0.93	0.031	0.959	0.759	0.743
Thymus weight/BW	2.31	2.51	2.48	2.34	0.061	0.610	0.897	0.190
Bursa of Fabricius weight/BW	0.84b	1.19a	0.93b	0.91b	0.039	0.026	0.856	0.009

BW, body weight. Values are presented as the mean with SEM (n = 8). Means with unlike superscript letters in the same row are significantly different (P < 0.05).