Table 5.

Effects of increasing concentrations of an E. coli phytase on the apparent total tract digestibility (ATTD) of DM, GE, NDF, and ADF, and concentration of DE in corn-soybean meal–based diets fed to growing pigs

Item			Phytase, FTU1 per kilogram complete feed				SEM	P-value2
	PC3	NC	500	1,000	2,000	4,000		PC vs. NC	Linear	Quadratic
ADFI, kg/d	1.75	1.73	1.76	1.73	1.72	1.75	0.15	0.452	0.963	0.513
GE intake, kcal/d	6,922	6,974	7,090	6,949	6,876	6,993	597.48	0.645	0.690	0.314
Dry feces output, kg/d	0.20	0.17	0.16	0.16	0.16	0.16	0.02	0.033	0.450	0.348
Fecal GE output, kcal/d	913	813	795	810	782	806	85.82	0.084	0.919	0.657
ATTD, GE %	86.88	88.34	88.80	88.38	88.68	88.44	0.51	0.050	0.966	0.721
ATTD, DM %	89.64	90.91	91.64	91.35	91.70	91.85	0.38	0.020	0.142	0.476
ATTD, NDF %	64.37	60.14	61.05	61.44	68.12	61.29	1.73	0.091	0.363	0.008
ATTD, ADF %	65.05	66.09	64.91	62.02	71.93	73.75	1.65	0.658	<0.001	0.719
DE in diet, kcal/kg
As-fed basis	3,429	3,559	3,580	3,549	3,540	3,542	20.42	<0.001	0.327	0.686
DM basis	3,945	4,095	4,127	4,076	4,068	4,081	23.49	<0.001	0.340	0.407

Data are means of 8 observations per treatment.

¹FTU = phytase units.

²Linear and quadratic contrasts of adding 500, 1,000, 2,000, or 4,000 FTU/kg phytase to the negative control diet.

³PC = positive control; NC = negative control.