Table 4.

Egg quality parameters of laying hens fed different lignocellulose levels at 38 wk of age.

Items	Supplementation amount (kg/ton of feed)				Pooled SEM	P-values
	0	0.5	1	2		Fixed	Linear	Quadratic
Egg quality parameters
Eggshell breaking strength (kg/cm2)	2.14c	3.32a	3.60a	2.71b	0.40	<0.001	0.144	<0.001
Eggshell thickness (mm)	0.417c	0.431b	0.476a	0.428b	0.01	<0.001	0.126	<0.001
Yolk index (%)	51.4a,b	52.1a	52.9a	50.5b	1.6	0.001	0.107	<0.001
Albumen index (%)	11.0a	11.1a	11.4a	10.0b	0.9	0.001	0.004	0.004
Haugh unit	88.1	89.6	90.3	87.6	3.5	0.113	0.533	0.018
Egg content
Yolk ratio (%)	23.8b	24.4b	25.7a	24.3b	1.1	<0.001	0.261	<0.001
Albumen ratio (%)	66.2a	66.6a	64.3b	66.1a	1.5	0.001	0.440	0.017
Eggshell ratio (%)	9.5	9.0	9.8	9.6	1.6	0.408	0.903	0.513

^a,b,cMeans bearing different superscripts within the same line are significantly different.

n: 25 eggs per treatment group.