Table 1.

Ingredients and nutrient composition of the experimental diets (as-fed basis).

Item	Phase I (d 1–14)		Phase II (d 15–42)
	Normal	Low	Normal	Low
Ingredient, %
Corn (CP 7.8%)	31.20	32.65	66.00	67.40
Corn, extruded (CP 7.8%)	27.00	27.00
Soybean meal (46%)	9.00	7.50	20.00	18.50
Soybean meal extruded	8.00	8.00
Soy protein concentrate	7.00	7.00	1.50	1.50
Fish meal (CP 62.5%)	3.00	3.00	3.00	3.00
Whey powder (CP 3%)	8.00	8.00	3.00	3.00
Sucrose	2.00	2.00	2.00	2.00
Soybean oil	1.70	1.60	1.70	1.60
Choline chloride	0.10	0.10	0.10	0.10
NaCl	0.30	0.30	0.30	0.30
Vitamin premix a	0.05	0.05	0.05	0.05
Mineral premix b	0.30	0.30	0.30	0.30
Limestone	0.75	0.75	0.70	0.71
Dicalcium phosphate	0.85	0.86	0.72	0.75
L-Lysine-HCl	0.44	0.44	0.37	0.37
DL-Methionine	0.16	0.16	0.14	0.14
L-Threonine	0.14	0.11	0.11	0.08
L-Tryptophan	0.01	0.01	0.01	0.01
Nutrient levels c
DE, MJ/kg	14.78	14.78	14.32	14.32
CP, %	18.82	18.24	17.81	17.23
Ca, %	0.80	0.80	0.70	0.70
Total P, %	0.65	0.65	0.60	0.60
Available P, %	0.46	0.46	0.39	0.40
DLys, %	1.35	1.31	1.23	1.19
DMet, %	0.46	0.45	0.43	0.42
DMet + DCys, %Dcys(%)	0.74	0.72	0.68	0.66
DThr, %	0.79	0.76	0.73	0.70
DTrp, %	0.22	0.21	0.20	0.20

^a Vitamin premix provided the following quantities of vitamins per kilogram of a complete diet: vitamin A, 15,000 IU; vitamin D₃, 5000 IU; vitamin E, 40 IU; vitamin K₃, 5 mg; vitamin B₁, 5 mg; vitamin B₂, 12.5 mg; vitamin B₆, 6 mg; vitamin B₁₂, 0.06 mg; niacin, 50 mg; folic acid, 2.5 mg; biotin, 0.25 mg; pantothenic acid, 25 mg. ^b Mineral premix provided the following quantities of minerals per kilogram of complete diet: Fe 100 mg (FeSO₄·H₂O); Cu 6 mg (CuSO₄·5H₂O); Mn 4 mg (MnSO₄·H₂O); Zn 100 mg (ZnSO₄·H₂O), 1600 mg (ZnO); I 0.14 mg (KI); Se 0.30 mg (Na₂SeO₃). ^c Nutrient levels are theoretical values except the CP was measured value.