Table 2.

Effects of different ZnO sources on growth performance and fecal score in weanling pigs

Item	CL1)	HME1) (ppm)			P-ZnO1)	SEM	Contrasts2) (p-value)
		500	1,000	2,500			CL vs others	HME vs P-ZnO	L	Q
Phase 1 (0–14 d)
ADG (g)	255	261	281	289	285	5.58	0.009	0.293	<0.001	0.888
ADFI (g)	379	377	393	402	395	10.62	0.316	0.706	0.088	0.599
G:F	0.67	0.70	0.71	0.72	0.72	0.01	0.004	0.456	0.700	0.419
Phase 2 (15–28 d)
ADG (g)	399	442	443	435	448	5.32	<0.001	0.229	<0.001	<0.001
ADFI (g)	623	635	658	644	657	11.68	0.065	0.391	0.073	0.195
G:F	0.64	0.66	0.67	0.67	0.68	0.01	<0.001	0.042	<0.001	0.074
Overall (0–28 d)
ADG (g)	327	351	362	362	367	4.32	<0.001	0.137	<0.001	0.031
ADFI (g)	501	506	526	523	526	8.21	0.078	0.432	0.041	0.673
G:F	0.66	0.68	0.69	0.69	0.7	0.01	<0.001	0.103	<0.001	0.180
Fecal score3)
Phase 1	3.81	2.84	3.09	2.79	2.63	0.15	<0.001	0.006	<0.001	0.011
Phase 2	2.69	2.34	1.88	1.72	1.39	0.10	<0.001	<0.001	<0.001	0.384

HME, hot melt extrusion; SEM, standard error of means; ADG, average daily gain; ADFI, average daily feed intake; G:F, gain to feed ratio.

¹⁾CL, basal diet without ZnO; HME, basal diet with 500, 1,000, and 2,500 ppm Zn as HME-ZnO; P-ZnO, Basal diet with 2,500 ppm Zn as ZnO.

²⁾Linear (L) and quadratic (Q) effects of HME concentrations.

³⁾1 = hard feces, 2 = firm well formed, 3 = soft and partially formed feces, 4 = loose, semi-liquid feces, and 5 = watery feces.