Table 4.

Color values of breast meat (15 min and 24 h postmortem) of broiler chickens at 42 d age fed with diets containing different vitamin A supplementation.

		Vitamin A (IU/Kg)
	Supplementation1	0	6,000	16,000	26,000	36,000	46,000	Average2	SEM	P (Anova)	P (Test F)	P (Regression)
L* (15 min)	T – 21	53.399	51.720	50.911	50.125	43.970	50.726	50.142	7.1902800	0.1776	0.3337	0.2943
	T – 42	51.216	50.570	50.008	49.375	5.343	48.911	50.071	4.878980	0.9457		0.8760
a* (15 min)	T – 21	4.415	6.606	5.484	5.550	5.636	6.116	5.634	2.449553	0.6134	0.5119	0.8164
	T – 42	7.790	4.995	7.381	4.854	6.349	4.953	6.053	3.687036	0.4201		0.8804
b* (15 min)	T – 21	7.430	8.718	6.709	6.069	6.074	7.503	7.085	2.945354	0.4609	0.0214	0.2253
	T – 42	7.330	5.016	6.753	4.984	6.030	3.243	5.559	3.335864	0.1955		0.5469
L* (24 h)	T – 21	60.020	56.755	56.208	55.726	53.506	58.583	56.799	4.192089	0.0566	0.6830	0.0517
	T – 42	59.189	56.334	55.199	54.804	58.403	54.571	56.416	4.558684	0.2193		0.4115
a* (24 h)	T – 21	4.699	7.100	5.950	6.935	6.096	5.345	6.0208	2.31273	0.2986	0.8959	0.0890
	T – 42	6.644	5.579	6.215	6.128	6.113	5.814	6.082	2.31187	0.9615		0.9704
b* (24 h)	T – 21	10.436	8.850	7.910	8.591	7.291	9.103	8.697	2.692618	0.2888	0.0061	0.0793
	T – 42	9.381	5.579	7.050	6.001	7.031	5.989	7.054	2.93487	0.2338		0.3013

L, linear; Q, Quadratic.

L* = lightness; a* = redness; b* = yellowness.

¹T-21d: birds supplemented with treatments in the period of the 4 to 21 days of age; T-42 d: birds supplemented with treatments in the period of the 4 to 42 days of age.

²Test F (P ≤ 0.05) for comparing the averages of vitamin A supplementation times.