Table 3. Phenotypic values and effects of the g.420 C>A polymorphism of the cholecystokinin type A receptor gene on the growth traits of improved and conventional Hinai-jidori chickens.

	Improved Hinai-jidori (n=30) 1		Conventional Hinai-jidori (n=63) 2			additive effects		dominance effects
Items	Mean±SE		Mean±SE		Intercept ±SE	Mean±SE		Mean±SE		Fvar	Rvar	Variance (%)
BW-0 week (g)	38.9±0.6		38.7±0.3		37.7±0.7	0.6±0.4	n.s.	0.8±0.6	n.s.	733	709	3.0
BW-4 week (g)	333.6±5.4		327.6±4.2		321.1±8.0	6.2±4.7	n.s.	2.6±6.4	n.s.	94003	92150	2.0
BW-14 week (g)	1,821.4±19.3		1,779.6±16.9		1694.6±29.6	67.0±17.3	***	31.9±26.9	n.s.	1470420	1259837	14.3
BW-22 week (g)	2,719.8±33.6	a	2,623.0±27.6	b	2520.3±50.4	99.4±29.4	**	13.2±45.8	n.s.	4149494	3662051	11.7
ADG 0–4 week (g/day)	10.5±0.2		10.3±0.1		10.1±0.3	0.2±0.2	n.s.	0.1±0.2	n.s.	114	112	1.8
ADG 4–14 week (g/day)	21.3±0.3		20.7±0.2		19.6±0.4	0.9±0.2	***	0.4±0.3	n.s.	243	207	14.6
ADG 14–22 week (g/day)	16.0±0.3	a	15.1±0.3	b	14.7±0.6	0.6±0.4	n.s.	−0.3±−0.6	n.s.	578	555	4.1
ADG 0–22 week (g/day)	17.4±0.2	a	16.8±0.2	b	16.1±0.3	0.6±0.2	**	0.1±0.3	n.s.	174	154	11.7

¹Allele frequency: A, 1.0; C/C, 0.0.

²Allele frequency: A, 0.484; C, 0.516.

BW-0 week, BW-4 weeks, BW-14 weeks, and BW-22 weeks: Body weight measured at 0, 4, 14, and 22 weeks of age. ADG 0–4 week, ADG 4–14 weeks, ADG 14–22 weeks, and ADG 0–22 weeks: average daily gain between 0 and 4, between 4 and 14, between 14 and 22, and between 0 and 22 weeks of age. SE: standard error, n.s.: not significant, F_var: residual variance from the full model, R_var: residual variance from the reduced model, variance (%)=100×(1−R_var/F_var).

^a,bWithin a row, different superscripted letters denote a significant difference (P<0.05).

^**P<0.01

^***P<0.001.