Table 4.

Effect of APO on egg quality of broiler breeders with different egg laying rates.

Item1		Eggshell strength, kg/cm3	Albumen height, mm	Yolk color	Haugh unit	Yolk weight ratio, %	Eggshell weight ratio, %	Eggshell thickness, mm−2	Albumen weight ratio, %
Laying	APO
AR	−	3.68	6.01	8.07	74.6	33.67	9.68	30.70	56.65
AR	+	3.07	7.21	8.13	82.31	33.25	10.03	28.61	56.72
LR	−	3.45	6.38	8.40	76.49	33.81	10.01	29.52	56.18
LR	+	3.44	6.97	8.44	79.49	33.05	9.97	30.18	56.98
SEM		0.19	0.30	0.17	1.98	0.36	0.15	0.55	0.36
P-value		0.17	0.03	0.29	0.04	0.40	0.32	0.05	0.46
Main effect
Laying	AR	3.38	6.61	8.10	78.45	33.46	9.85	29.66	56.69
	LR	3.45	6.68	8.42	77.99	33.43	9.99	29.85	56.58
APO	−	3.56	6.2	8.23	75.55	33.74	9.84	30.11	56.42
	+	3.26	7.09	8.28	80.90	33.15	10.00	29.40	56.85
SEM		0.13	0.21	0.12	1.40	0.25	0.11	0.39	0.25
P-value
Laying		0.71	0.82	0.06	0.81	0.93	0.37	0.73	0.77
APO		0.11	<0.01	0.76	0.01	0.10	0.31	0.20	0.23
Laying∗APO		0.12	0.32	0.95	0.24	0.64	0.19	0.31	0.31

Abbreviations: APO, 200 mg/kg apple pectic oligosaccharide; AR, average egg laying rate; LR, low egg laying rate.

¹Each mean represents 4 eggs/replicate, 8 replicates/treatment.