Table 3.

Effect of phytase, age, and feeding length on nutrient digestibility and retention responses of broiler chickens

Age, D	Feeding length, day	Diet2	AID1 DM, %	AID P, %	AID Ca, %	TTR1 DM, %	TTR P, %	TTR Ca, %	Number of replicates
14	2 (days 12 to 14)	PC	72.0	56.0	58.2	66.5	50.1	44.7	8
14	2 (days 12 to 14)	NC	70.0	45.7	46.0	65.8	35.1	27.0	8
14	2 (days 12 to 14)	2,000	71.3	69.6	62.9	69.3	58.2	42.6	8
14	5 (days 9 to 14)	PC	70.2	55.0	59.6	70.0	54.9	45.0	8
14	5 (days 9 to 14)	NC	69.2	47.3	52.3	69.5	46.4	24.4	8
14	5 (days 9 to 14)	2,000	71.2	65.2	62.7	70.3	63.0	36.9	8
22	2 (days 20 to 22)	PC	70.7	54.4	50.4	69.6	48.9	46.2	8
22	2 (days 20 to 22)	NC	69.7	48.5	44.7	69.6	37.5	28.6	8
22	2 (days 20 to 22)	2,000	72.0	67.3	54.5	71.3	58.3	45.0	8
22	5 (days 17 to 22)	PC	71.1	58.3	57.5	71.4	51.8	45.5	8
22	5 (days 17 to 22)	NC	70.2	48.8	49.0	71.3	43.7	29.0	8
22	5 (days 17 to 22)	2,000	72.8	66.4	56.1	73.2	63.5	40.2	8
		PC	71.0	55.9	56.4	69.40	51.4	45.4	32
		NC	69.8	47.5	48.0	69.1	40.6	27.2	32
		2,000	71.8	67.1	59.0	71.0	60.8	41.1	32
14			70.6	56.4	57.0	68.6	51.3	36.7	48
22			71.1	57.3	52.0	71.1	50.6	39.1	48
	2		71.0	57.0	52.8	68.7	48.0	39.0	48
	5		70.8	56.8	56.2	71.0	53.9	36.8	48
14	2		71.1	57.1	55.7	67.2	47.8	38.1	24
14	5		70.1	55.8	58.2	70.0	54.8	35.4	24
22	2		70.8	56.7	49.9	70.2	48.2	40.0	24
22	5		71.3	57.8	54.2	72.0	53.0	38.2	24
P values
Diet			<0.01	<0.01	<0.01	<0.01	<0.01	<0.01
Age			0.25	0.51	<0.01	<0.01	0.47	0.17
Feeding Length			0.66	0.95	0.04	<0.01	<0.01	0.20
Diet × Age			0.39	0.68	0.43	0.90	0.51	0.86
Diet × Feeding length			0.60	0.34	0.47	0.54	0.07	0.45
Age × Feeding length			0.06	0.34	0.57	0.37	0.23	0.77
Diet × Age × Feeding length			0.81	0.66	0.62	0.46	0.47	0.89
PC vs. NC			0.01	<0.01	<0.01	0.63	<0.01	<0.01
NC vs. 2,000			<0.01	<0.01	<0.01	<0.01	<0.01	<0.01
Days 12 to 14 vs. 9 to 14			0.11	0.47	0.27	<0.01	<0.01	0.27
Days 20 to 22 vs. 17 to 22			0.31	0.52	0.06	0.02	<0.01	0.48
Days 12 to 14 vs. 20 to 22			0.61	0.83	0.01	<0.01	0.73	0.44
Days 9 to 14 vs. 17 to 22			0.04	0.26	0.08	<0.01	0.18	0.24

¹AID = apparent ileal digestibility; TTR = total tract retention; DM = dry matter; P = phosphorus; Ca = calcium.

²PC = positive control; NC = negative control; 2,000 = NC + 2,000 phytase units/kg.