Effects of graded levels of CHC on serum hormones in weaned piglets^a (n = 6).

Items	MMT, mg kg−1, 1000	CHC, mg kg−1						SEM	P value
		0		500	1000	1500	2000		ANOVA	Linear	Quadratic
14 d b
GH, ng mL−1	6.95	7.50	7.32		7.21	7.52	7.75	0.41	0.81	0.89	0.82
INS, μIU mL−1	11.72	11.98	11.89		11.75	11.40	10.20	1.18	0.90	0.63	0.49
IGF-1, ng mL	156.01b	141.38c	173.37a		170.46a	155.42b	152.57b	2.87	<0.01	0.14	0.48
COR, μg dL−1	5.44	5.04	5.40		5.50	5.60	5.57	0.92	0.99	0.77	0.67
28 d
GH, ng mL−1	7.12	7.56	7.28		7.56	7.59	7.76	0.44	0.92	0.82	0.65
INS, μIU mL−1	13.19	12.17	12.31		11.90	12.25	12.12	1.21	0.98	0.89	0.91
IGF-1, ng mL	154.38	152.35	166.13		164.72	149.34	149.78	5.39	0.13	0.86	0.17
COR, μg dL−1	7.21	6.95	6.80		6.63	6.56	6.84	0.17	0.99	0.98	0.84

^{a a,b,c}Means within the same row without common superscripts differ significantly (P < 0.05).

^bGH growth hormone, INS insulin, IGF-1 insulin-like growth factor-I, COR cortisol.