Table 3.

Ingredient composition of experimental diets (as-fed basis)

Ingredient, %	Phase 1		Phase 2		Phase 3
	Negative control	Positive control	Negative control	Positive control	Negative control	Positive control
Basal mix	96.52	96.52	98.43	98.43	98.75	98.75
Corn	3.35	2.52	1.46	0.63	1.10	0.25
Soybean meal	0.02	0.03	0.01	0.07	—	0.05
Limestone	—	0.73	—	0.08	—	0.08
Monocalcium P	—	0.05	—	0.70	—	0.75
Sanda	0.10	0.15	0.10	0.10	0.15	0.13
Phytaseb	—	—	—	—	—	—
Calculated analysis
CP, %	22.8	22.8	22.2	22.2	21.2	21.3
Ca, %	0.71	0.85	0.66	0.80	0.56	0.70
P, %	0.66	0.81	0.63	0.77	0.61	0.76
Ca:P ratio	1.07	1.05	1.05	1.04	0.93	0.92

^aSand was used to displace phytase in the diet as inclusion rate varied; as a result, the same amount of basal mix in each phase was added to each of the treatment diets.

^bNatuphos E 5,000 G (BASF Corporation, Florham Park, NJ) was added to the negative control to achieve experimental diets with 0, 500, 1,000, 2,000, 3,000, or 4,000 FTU/kg or was added to positive control diet to achieve experimental diets with 0 or 2,000 FTU/kg. Phytase inclusion was determined using the analyzed concentration, and the phytase contained 5,111,000 FTU/kg.