Growth and slaughtering performance, carcase fleshiness and meat quality according to the plumage colour in Padovana male chickens slaughtered at 18 weeks of age

Figures & data

Table 1. Formulation and chemical composition of the feed.

Ingredients	%	Chemical composition	%
Corn meal	48.0	Dry matter	87.5
Soybean	23.0	Crude protein	21.0
Corn flour	17.4	Crude fat	5.1
Corn gluten meal	5.0	Crude fibre	4.5
Soybean oil	2.5	Ash	7.2
Calcium carbonate	2.0	Ca	1.7
Bicalcium phosphate	1.5	P	1.8
Sodium chloride	.30	Lisine	.92
Supplement^a	.30	Methionine	.42
DL-methionine	.05	ME^b (kcal/kg)	2,847

^a Integration per kg: vitamin A 15,000 U; vitamin D₃ 3,000 U; vitamin E (α-tocoferol 91%) 30 mg; vitamin B₂ 35 mg; Cu (Cu sulphate) 10 mg.

^b Metabolisable Energy.

Figure 1. Environmental temperature (T) and relative humidity (RH) patterns according to the age of the chickens. Age: is referred to the weeks of life; II (5–7th week); III (8–10th weeks); IV (11–13th week); V (14–16th week); VI (17–18th week).

Table 2. Daily growth and heterosis according to the age of the chickens.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Body gain^3, g/d
3–4th week	8.13^Aa	4.73^Cc	7.24^AaBb	5.78^BbCc	<.0001	2.30	12.6	−10.1
5 –6th week	13.5^Aa	8.7^Cc	11.5^ABb	10.2^BbCc	<.0001	2.9	3.8	−9.0
7–8th week	15.4^Aa	11.9^Bb	15.0^Aa	14.9^Aa	<.0001	2.9	9.9	4.0
9–10th week	13.8^Bb	13.9^ABb	16.4^Aa	16.5^Aa	.0006	3.0	18.8	19.6
11–14th week	19.1	18.6	19.4	19.6	.5906	2.6	3.5	4.0
15–18th week	15.6^b	15.8^ab	16.6^ab	18.2^a	.0570	3.4	5.7	15.9

^a,b,cMeans within the same row followed by different superscript letters differ p < .05.

^A,B,CMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (36 birds); PS: Padovana silver (23 birds); Cross-W: cross white (26 birds); Cross-S: cross silver (18 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Age: the body gain was calculated on period of 2 or 4 weeks according to the age that is referred to the weeks of life.

Table 3. Body weight and heterosis according to the age of the chickens.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Body weight^3, g
6th week	406^Aa	249^Cc	354^ABb	294^BbCc	<.0001	77	8.1	−10.5
8th week	607^Aa	404^Cc	549^AaBb	489^BbC	<.0001	100	8.6	−3.1
10th week	801^Aa	598^Bc	778^Aab	710^ABb	<.0001	117	11.2	1.4
14th week	1320^Aa	1099^Bb	1303^Aa	1239^Aa	<.0001	121	7.7	2.4
18th week	1744^Aa	1513^Bb	1751^Aa	1729^Aa	<.0001	137	7.5	6.1

^a,b,cMeans within the same row followed by different superscript letters differ p < .05.

^A,B,CMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (36 birds); PS: Padovana silver (23 birds); Cross-W: cross white (26 birds); Cross-S: cross silver (18 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Age: the age is referred to the week of life.

Table 4. Slaughtering performance.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Cold carcase^3, g	1335^a	1218^b	1324^ab	1314^ab	.0314	84	3.7	2.9
Dressing^4, %	74.6^ab	76.6^a	73.6^b	73.2^b	.0101	2.0	−2.7	−3.2
Commercial cuts, g
Breast	235^Aa	201^Bb	229^Aa	249^Aa	<.0001	17	5.1	14.2
Wings	160	157	160	161	.9573	14	1.0	1.6
Legs	406^AaB	370^Bb	415^AaB	418^Aa	.0079	28	7.0	7.7
Cold carcase^5, %
Head and neck	10.6^a	10.20^ab	10.9^a	9.24^b	.0152	.94	4.8	−11.2
Shanks	4.52^Bb	5.16^Aa	4.67^AaBb	4.65^ABb	.0061	.36	−3.5	−3.9

^a,bMeans within the same row followed by different superscript letters differ p < .05.

^A,BMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (10 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Slaughtering body weight after removal of blood, feathers and viscera, and refrigeration.

⁴ (Cold carcase weight/slaughtering body weight) × 100.

⁵ (Head and neck weight, and shanks weight/carcase weight) × 100.

Table 5. Carcase yield.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Ready-to-cook carcase^3, %
Breast	20.8^ab	19.5^b	20.5^ab	22.0^a	.0505	1.6	1.7	9.2
Wings	14.1	15.3	14.3	14.2	.1196	1.1	−2.7	−.3
Legs	35.8	35.9	37.1	32.6	.1615	3.8	3.5	−9.1
Fleshiness, g
Wings^4	89.3	81.7	86.0	87.5	.1930	7.4	0.6	2.3
Legs^5	313^Bb	279^Bc	320^AaBb	325^Aa	.0076	26	8.1	9.8
Total^6	637^Aa	562^Bb	636^Aa	662^Aa	.0002	39	6.1	10.4
Total^7, %	56.3^AaBb	54.4^Bb	56.8^AaBb	58.6^Aa	.0126	2.2	2.6	5.9

^a,b,cMeans within the same row followed by different superscript letters differ p < .05.

^A,B,CMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (10 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Cold carcase (slaughtering body weight after removal of blood, feathers and viscera, and refrigeration) without head and neck, shanks, and giblets (heart, liver and gizzard).

⁴ Drumette and wingette (skin and muscles).

⁵ Thighs and drumsticks (skin and muscles).

⁶ Breasts, wings and hindlegs.

⁷ (Total fleshiness weight/ready-to-cook carcase) × 100.

Table 6. Wing traits.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Drumette, g	36.2	33.0	34.0	34.2	.3178	3.4	−1.7	−1.2
Wingette, g	29.3	28.3	29.6	28.3	.5628	2.0	2.8	−1.7
Tip, g	9.53	9.21	9.59	9.62	.5570	.62	2.4	2.7
Meat:bone ratio^3
Drumette	1.81	1.87	1.89	1.99	.3181	.18	2.7	8.2
Wingette	2.58	2.36	2.34	2.45	.1294	.22	−5.3	−.8
Total^4	2.11	2.07	2.08	2.18	.6352	.17	−.5	4.3

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (8 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Muscles and skin:bone ratio.

⁴ Drumette and wingette.

Table 7. Leg traits.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
Thigh, g	117^a	102^b	117^a	118^a	.0098	10	6.9	7.8
Drumstick, g	85.4^ab	81.7^b	89.4^a	86.9^ab	.0615	5.3	7.0	3.9
Meat:bone ratio
Thigh	5.05^AaB	4.02^Bb	5.22^AaB	5.66^Aa	.0013	0.73	15.1	24.8
Drumstick	2.45	2.58	2.75	2.79	.1989	0.36	9.3	10.9
Total^3	3.56^AaB	3.22^Bb	3.85^AaB	4.03^Aa	.0079	0.45	13.6	19.2
Thigh, %
Muscle	72.5^Aa	68.3^Bb	73.1^Aa	75.1^Aa	.0002	2.5	3.8	6.7
Bone	14.6^ABb	17.5^Aa	14.2^Ab	13.4^Bb	.0046	2.2	−11.5	−16.5
Drumstick, %
Muscle	63.7	63.6	62.7	64.7	.8583	4.4	−1.5	1.7
Bone	29.8	28.4	28.4	26.9	.2738	2.9	−2.4	−7.6

^a,bMeans within the same row followed by different superscript letters differ p < .05.

^A,BMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations- PC: Padovana chamois (10 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ Thigh and drumstick.

Table 8. Colour traits of breast and thigh.

	Parental genotypes^1		Offspring genotypes^1		p value	RMSE
	PC	PS	Cross-W	Cross-S
Breast^2
Skin
L*	64.3	64.6	65.6	64.4	.7725	2.7
a*	.002	−.063	.197	−.313	.5463	.657
b*	−1.08^ab	.915^a	.012^ab	−2.10^b	.0185	1.92
Muscle^3
L*	52.8	54.9	54.1	52.9	.4616	3.3
a*	1.65	.887	.815	1.03	.0922	.763
b*	.559	2.05	2.08	1.81	.1948	1.71
Thigh^2
Skin
L*	69.1	71.2	69.3	68.9	.3609	3.0
a*	1.38^a	1.37^a	.887^ab	−.174^b	.0276	1.09
b*	5.70	5.83	4.45	4.00	.2466	2.15
Muscle^4
L*	50.80	51.4	51.1	51.1	.9808	3.0
a*	2.75^Bb	5.10^Aa	2.44^Bb	2.76^Bb	.0001	1.22
b*	1.28^b	2.29^ab	1.98^ab	4.37^a	.0300	2.00

^a,bMeans within the same row followed by different superscript letters differ p < .05.

^A,BMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (10 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² L*: lightness index; a*: redness index; b*: yellowness index.

³ Pectoralis major muscle.

⁴ Ilio tibialis muscle.

Table 9. Chemical and rheological traits of breast meat.

	Parental genotypes^1		Offspring genotypes^1				Heterosis^2
	PC	PS	Cross-W	Cross-S	p value	RMSE	Cross-W	Cross-S
pH - 48h	5.95	5.85	5.95	5.96	.2535	.12	.9	1.0
Crude protein^3, % DM	94.7	94.7	94.3	94.1	.3884	.8	−.4	−.6
Total lipids^3, % DM	1.44	.79	1.42	1.01	.1784	.69	27.4	−9.4
Ash^3, % DM	4.59^a	4.36^ab	4.40^ab	4.31^b	.0295	.2	−1.7	−3.7
Thawing losses, %	4.92^Bb	9.32^Aa	7.64^AaBb	7.20^AaBb	.0033	2.27	7.3	1.1
Cooking losses, %	19.9^b	23.6^a	21.1^ab	20.7^a	.0348	2.5	−3.0	−4.8
Total losses, %	24.9^Bb	32.9^Aa	28.7^AaBb	27.9^AaBb	.0040	4.2	−.4	−3.5
Shear force, N	12.2^b	16.5^a	15.5^ab	12.8^ab	.0295	3.2	8.0	−10.8

^a,bMeans within the same row followed by different superscript letters differ p < .05.

^A,BMeans within the same row followed by different superscript letters differ p < .01.

RMSE: root mean square error.

¹ Genotypes and number of observations - PC: Padovana chamois (10 birds); PS: Padovana silver (8 birds); Cross-W: cross white (7 birds); Cross-S: cross silver (7 birds).

² % heterosis: [Cross-W or Cross-S − (PC + PS)/2]/[(PC + PS)/2] × 100.

³ DM: dry matter.