Table 1. Ingredients and nutrient content of the basal diets.

Item	Diets
	Normal protein	Low protein
Ingredient (%)
Maize	75.43	76.50
Soybean meal	11.79	3.50
Cottonseed meal	4.00	0.70
Wheat bran	4.00	9.00
Soybean oil	1.60	0.15
Maize starch	—	6.0
L-Lysine-HCL	0.28	0.55
DL-methionine	0.02	0.11
L-threonine	0.07	0.20
L-tryptophan	0.01	0.05
L-valine	—	0.11
L-phenylalanine	—	0.05
L-isoleucine	—	0.13
Dicalcium phosphate	0.65	0.65
Limestone	0.85	1.00
Salt	0.30	0.30
Premix †	1.00	1.00
Analyzed nutrient level
Crude protein (%)	14.06	10.05
Calculated nutrient level
Net energy (MJ/kg)	10.38	10.37
Available phosphorus (%)	0.25	0.24
Calcium (%)	0.52	0.55
Standardized ileal digestible amino acids (%) ‡
Lysine	0.73	0.73
Methionine+Cysteine	0.42	0.42
Threonine	0.46	0.46
Tryptophan	0.13	0.13
Valine	0.54	0.48
Phenylalanine	0.59	0.44
Leucine	1.06	0.80
Isoleucine	0.42	0.39

CP, crude protein.

^†The premix provided per kilogram of diet: 100 mg of zinc as zinc oxide, 100 mg of iron as iron sulphate, 30 mg of manganese as manganous oxide, 0.3 mg of selenium as sodium selenite, 20 mg of copper as copper sulphate, 0.5 mg of iodine as calcium iodate, 1720 μg retinyl acetate, 8.0 mg DL-α-tocopheryl acetate, 25 μg cholecalciferol, 3.0 mg menadione sodium bisulphite, 3.0 mg pyridoxine hydrochloride, 2.0 mg thiamin mononitrate, 6.0 mg riboflavin, 1.0 mg folic acid, 20 μg cyanocobalamin, 30 mg nicotinic acid, 30 mg calcium pantothenate, 300 mg choline.

^‡Values for standardized ileal concentrations of AA were calculated using standardized ileal digestible coefficients provided by Xiong et al., [28]