Table 7.

Effects of dietary addition of Echinacea purpurea polysaccharides (EP) on SCFA in the caecum of broilers.

Items	Age, d	Groups1				SEM	P-value
		CON	EPL	EPM	EPH		ANOVA	Linear	Quadratic	EPs × age
pH	21	7.53	7.38	7.32	7.54	0.057	0.464	0.951	0.271	0.507
	42	7.68	7.38	7.38	7.28	0.081	0.346	0.117	0.240
Acetic acid, mmol/L	21	7.53b	11.46ab	13.81a	10.99ab	0.848	0.047	0.143	0.021	0.740
	42	10.24b	10.91ab	16.14a	13.90ab	0.968	0.013	0.062	0.095
Propionic acid, mmol/L	21	0.70b	0.99ab	1.69a	0.89bB	0.106	0.029	0.539	0.096	0.472
	42	1.41b	1.76ab	2.73a	2.57abA	0.225	0.047	0.025	0.055
Butyric acid, mmol/L	21	1.30b	1.22b	3.13a	1.67ab	0.282	0.036	0.254	0.137	0.728
	42	1.70b	1.95ab	3.02a	2.35ab	0.201	0.037	0.106	0.087
Isobutyric acid, mmol/L	21	0.16	0.12	0.18	0.10B	0.018	0.415	0.499	0.622	0.054
	42	0.19b	0.26b	0.36ab	0.43aA	0.032	0.025	0.002	0.008
Valeric acid, mmol/L	21	0.19	0.15B	0.17B	0.12B	0.018	0.613	0.250	0.525	0.195
	42	0.34	0.36A	0.46A	0.45A	0.031	0.187	0.027	0.091
Isovaleric acid, mmol/L	21	0.16B	0.18	0.13B	0.15B	0.014	0.863	0.668	0.914	0.257
	42	0.45A	0.37	0.49A	0.55A	0.048	0.159	0.033	0.098
Total SCFA, mmol/L	21	10.16b	15.04ab	19.74a	13.80abB	1.277	0.045	0.263	0.028	0.725
	42	14.24b	15.62ab	23.29a	20.33abA	1.437	0.044	0.043	0.068

SCFA = short-chain fatty acid; CON = control; SEM = standard error of the mean.

Different lowercase letter superscripts in the same row indicate significant differences among EP addition levels (0.0, 0.3%, 0.6%, and 0.9%) (P < 0.05). Different uppercase letter superscripts within the same column indicate significant differences between age stages (21 and 42 d) (P < 0.05); EPs × age denotes the interaction between EP addition levels and ages.

¹CON, EPL, EPM, and EPH, represent EP addition levels of 0.0, 0.3%, 0.6%, and 0.9% in the diet, respectively (n = 6).