Table 3.
Effects of dietary hydrolyzed yeast on egg and eggshell qualities in aged laying hens¹

	Hydrolyzed yeast (%)			SEM	P values
	0	0.1	0.2		Linear	Quadr.	ANOVA
Eggshell strength (kg/cm2)
1∼4 wk	4.1b	4.6a	4.5a	0.09	0.006	0.065	0.001
5∼8 wk	4.0b	4.6aͣ	4.6a	0.09	0.010	0.078	0.011
total period	4.0b	4.6a	4.6a	0.09	0.003	0.040	0.003
Eggshell thickness (mm)
1∼4 wk	0.380c	0.393b	0.407a	0.01	0.001	1.000	<0.001
5∼8 wk	0.377	0.393	0.395	0.01	0.035a	0.291	0.066
total period	0.378b	0.393a	0.402a	0.01	0.001	0.485	0.002
Haugh unit
1∼4 wk	89.4	88.7	88.3	0.83	0.770	0.606	0.835
5∼8 wk	83.9	85.3	85.1	1.53	0.574	0.667	0.772
total period	85.9	87.0	86.7	0.88	0.532	0.534	0.674
Yolk color
1∼4 wk	8.9b	9.2a	9.1ab	0.07	0.081	0.044	0.036
5∼8 wk	9.0	9.2	9.0	0.08	0.965	0.052	0.142
total period	8.9b	9.2a	9.0ab	0.08	0.262	0.017	0.033

Data are least square of mean of 6 replicate with 2 cages with 5 birds per cage.
Mean values within a row with different superscripts differ at P<0.05.