Table 1.

Composition of the experimental laying hen diet

Items	Dietary treatments
	LPS	–	–	+	+
	NPP,%	0.12	0.40	0.12	0.40
Ingredient, %
Corn		61.29	60.45	61.29	60.45
Soybean meal		27.21	27.29	27.21	27.29
Soybean oil		0.97	1.21	0.97	1.21
Limestone		9.73	8.59	9.73	8.59
Dicalcium phosphate		0	1.65	0	1.65
Salt		0.30	0.30	0.30	0.30
Trace mineral premixa		0.20	0.20	0.20	0.20
Vitamin premixb		0.02	0.02	0.02	0.02
DL-Methionine		0.16	0.17	0.16	0.17
Choline chloride		0.12	0.12	0.12	0.12
Total		100	100	100	100
Nutrient composition, %
ME, Mcal/kg		2.7	2.7	2.7	2.7
CP		17	17	17	17
Calcium		3.5	3.5	3.5	3.5
Nonphytate phosphorus (NPP)		0.12	0.40	0.12	0.40
Lysine		0.86	0.86	0.86	0.86
Methionine+Cystine		0.65	0.65	0.65	0.65
Tryptophan		0.21	0.21	0.21	0.21
Threonine		0.66	0.66	0.66	0.66

^aMineral premix provided per kilogram of diet: Mn, 100 mg; Fe, 80 mg; Zn, 75 mg; Cu, 8 mg; I, 0.35 mg; Se, 0.15 mg

^bVitamin premix provided per kilogram of diet: vitamin A, 12,500 IU; vitamin D₃, 2,500 IU; vitamin E, 30 IU; vitamin K₃, 2.65 mg; vitamin B₁, 2 mg; vitamin B₂, 6 mg; vitamin B₁₂, 0.025 mg; biotin, 0.0325 mg; folic acid, 1.25 mg; pantothenic acid, 12 mg; niacin, 50 mg