Table 5.

Breast meat pH and color properties of broiler chickens fed diets with different amino acid (AA) densities under different stocking densities from 0 to 49 d of age¹.

AA density2	Stocking density3	pH		24 h			48 h
		15 min	24 h	L∗	a∗	b∗	L∗	a∗	b∗
Norm	High	6.59	5.86	59.5	2.0	9.4a	59.2	1.9	9.3a,b
Norm	Low	6.56	5.81	58.4	2.2	8.1b	59.0	2.2	7.7b
10%Low	High	6.52	5.77	59.2	2.4	9.5a	59.9	2.4	9.5a
10%Low	Low	6.53	5.78	58.2	2.9	9.4a	58.8	2.5	9.4a
20%Low	High	6.53	5.74	60.4	2.5	8.8a,b	60.3	2.7	9.1a,b
20%Low	Low	6.61	5.74	61.3	2.5	9.7a	60.6	2.5	9.3a,b
SEM		0.029	0.020	0.625	0.263	0.447	0.595	0.209	0.405
AA density
NORM		6.57	5.83a	58.9b	2.1	8.7	59.1	2.0b	8.5
10%Low		6.53	5.77b	58.7b	2.6	9.5	59.4	2.5a,b	9.4
20%Low		6.57	5.74b	60.9a	2.5	9.2	60.4	2.6a	9.2
SEM		0.020	0.014	0.442	0.186	0.316	0.421	0.148	0.286
Stocking density
High		6.55	5.79	59.7	2.3	9.2	59.8	2.3	9.3
Low		6.57	5.78	59.3	2.5	9.1	59.5	2.4	8.8
SEM		0.017	0.012	0.361	0.152	0.258	0.344	0.121	0.234
P values
AA density		0.228	<0.001	0.001	0.122	0.243	0.062	0.029	0.057
Stocking density		0.357	0.427	0.446	0.345	0.675	0.479	0.691	0.137
AA density × stocking density		0.118	0.304	0.247	0.722	0.043	0.542	0.622	0.050
AA density linear		0.841	<0.001	0.003	0.160	0.272	0.026	0.011	0.081
AA density quadratic		0.089	0.450	0.031	0.133	0.202	0.433	0.435	0.097

^a,bMeans with different superscripts in a column differ significantly (P ≤ 0.05).

¹Means represent 6 replicates with 8 birds per replicate for each treatment.

²Norm = recommended amino acid (AA) density; 10%low = 10% lower than norm AA density; 20%low = 20% lower than norm AA density.

³High = 35 kg of body weight/m²; low = 26 kg of body weight/m² of stocking density.