Table 5.

Total tract nutrient retention of broilers fed diets adequate or deficient in aP and Ca, with zero, 500, or 1,500 FTU/kg phytase, for 21 days.

		Total tract retention coefficients
Diet		DM	N	P	Ca
		Simple effect means
Negative control (NC)		0.702	0.626	0.617	0.511
NC + 500 FTU/kg		0.734	0.679	0.703	0.569
NC + 1,500 FTU/kg		0.737	0.698	0.678	0.536
Positive control (PC)		0.729	0.699	0.581	0.513
PC + 500 FTU/kg		0.717	0.678	0.534	0.456
PC + 1,500 FTU/kg		0.718	0.674	0.568	0.446
SEM		0.007	0.011	0.023	0.029
		Main effect means
aP, %	0.35	0.724	0.668	0.666	0.539
	0.50	0.721	0.683	0.561	0.472
SEM		0.004	0.006	0.013	0.017
Phytase1	0	0.716	0.663	0.599	0.512
	500	0.725	0.678	0.618	0.512
	1,500	0.728	0.686	0.623	0.491
SEM		0.005	0.008	0.016	0.020
		P-values for main effects
aP, %		0.554	0.092	<0.001	0.008
Phytase		0.181	0.114	0.558	0.704
aP × phytase		0.002	<0.001	0.025	0.125
		P-values for orthogonal contrasts
PC linear		0.336	0.147	0.903
PC quadratic		0.320	0.360	0.147
NC linear		0.002	<0.001	0.155
NC quadratic		0.025	0.046	0.030

¹FTU/kg phytase.

8 replications per diet.

N: Nitrogen.

P: Phosphorus.

Ca: Calcium.