Table 3.

The mandibular ramus characteristics of crossed beaks (n = 6) and normal beaks (n = 3) in Beijing-You chickens at 28 d of age.

Group		Crossed beaks		Normal beaks	SEM	P-value
		LEFT	RIGHT	NORMAL
Mandible weight, g	Left	0.25	0.22B	0.23	0.01	0.37
	Right	0.27	0.25A	0.25	0.01	0.57
	SEM	0.01	0.01	0.01
	P-value	0.60	0.03	0.06
MR1 thickness, mm	Left	1.11A,a	0.83b	0.85b	0.06	0.04
	Right	0.84B,b	1.11a	0.84b	0.06	0.04
	SEM	0.07	0.09	0.01
	P-value	<0.01	0.07	0.69
MR width, mm	Left	3.78A	3.51B	3.47	0.06	0.05
	Right	3.51B,b	4.00A,a	3.46b	0.1	<0.01
	SEM	0.08	0.11	0.07
	P-value	<0.01	0.01	0.87
MR length, cm	Left	1.91B,b	2.59A,a	2.65a	0.12	<0.01
	Right	2.69A,a	1.91B,b	2.66a	0.13	<0.01
	SEM	0.18	0.16	0.03
	P-value	<0.01	<0.01	0.63
MR length difference (left-right), cm		−0.78c	0.68a	−0.01b	0.21	<0.01
Symmetry2, %		−16.91c	15.18a	−0.15b	4.64	<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.