Table 2.

The mandibular ramus characteristics of crossed beaks (n = 8) and normal beaks (n = 4) in Beijing-You chickens at 14 d of age.

Group		Crossed beaks		Normal beaks	SEM	P-value
		LEFT	RIGHT	NORMAL
Mandible weight, g	Left	0.15	0.16	0.17	0.01	0.52
	Right	0.16	0.17	0.18	0.01	0.62
	SEM	0.01	0.01	0.01
	P-value	0.32	0.41	0.38
MR1 thickness, mm	Left	1.03	0.87B	0.85	0.04	0.13
	Right	0.77c	1.06A,a	0.93b	0.05	0.01
	SEM	0.07	0.04	0.03
	P-value	0.07	0.01	0.12
MR width, mm	Left	2.64	2.96A	2.98	0.10	0.30
	Right	2.88	2.69B	2.98	0.07	0.24
	SEM	0.13	0.10	0.05
	P-value	0.23	<0.01	1.00
MR length, cm	Left	1.40B,b	2.09A,a	2.05a	0.10	<0.01
	Right	2.02A,a	1.52B,b	2.07a	0.08	<0.01
	SEM	0.12	0.11	0.01
	P-value	<0.01	<0.01	0.96
MR length difference (left-right), cm		−0.61c	0.57a	−0.02b	0.12	<0.01
Symmetry2, %		−18.05c	15.82a	−0.53b	2.78	<0.01

^a–cValues within a row with different superscripts differ significantly at P < 0.05.

^{A, B}Values within a column of each trait with different superscripts differ significantly at P < 0.05.

¹MR, Mandibular ramus.

²Symmetry (%) = (left MR length − right MR length)/(left MR length + right MR length) × 100.