Table 4. Egg quality.

VA Treatment (IU/kg)	Week 12 of experiment			Week 24 of experiment
	Yolk color	Eggshell thickness (µm)	Strength (kg/cm2)	Yolk color	Eggshell thickness (µm)	Eggshell strength (kg/cm2)
A (5,000)	8.72c	0.34	3.34	9.44c	0.36b	3.66
B (15,000)	8.33c	0.33	3.41	8.96bc	0.34a	3.19
C (45,000)	7.72b	0.34	3.31	8.37b	0.34a	3.47
D (135,000)	6.67a	0.33	3.26	6.18a	0.35a	3.64
SEM	0.132	0.001	0.091	0.202	0.002	0.104
P -value
Combined	<0.001	0.843	0.949	<0.001	0.034	0.281
Linear	<0.001	0.906	0.906	0.007	0.036	0.807
Quadratic	0.081	0.660	0.781	0.239	0.034	0.099

^a–cWithin a column, values not sharing a common superscript letter are significantly different (P<0.05).