Table 5.

Effects of breeding pigeon dietary supplementation with dl-Met or dl-Met-Met on the antioxidant activity of the thigh muscle of squabs^1,2.

Items3	Met Source	Met Dose	CAT (U/mg-prot)	T-SOD (U/mg-prot)	GSH-Px (U/mg-prot)	T-AOC (U/mg-prot)	MDA (nmol/mg-prot)
1	BD	0	0.70	20.54b	31.84b	0.40	0.84a
2	dl-Met	0.15%	0.79	24.36ab	37.81ab	0.44	0.78ab
3	dl-Met	0.30%	0.79	27.28a	39.99a	0.44	0.69bc
4	dl-Met	0.45%	0.78	26.98a	39.25a	0.43	0.70bc
5	dl-Met	0.60%	0.81	28.29a	38.96a	0.46	0.66c
6	dl-Met-Met	0.15%	0.77	26.20a	39.01a	0.45	0.72bc
7	dl-Met-Met	0.30%	0.80	28.66a	43.11a	0.44	0.70bc
8	dl-Met-Met	0.45%	0.79	28.38a	41.17a	0.45	0.70bc
9	dl-Met-Met	0.60%	0.84	28.36a	42.43a	0.44	0.66c
SEM			0.010	0.643	0.808	0.008	0.013
P-values
treatment effects			0.104	0.034	0.032	0.926	0.019
Met source			0.707	0.324	0.147	0.813	0.689
main effect of the Met source
dl-Met			0.79	26.73	39.25	0.44	0.71
dl-Met-Met			0.80	27.90	41.43	0.45	0.70
linear effect4
dl-Met			0.025	0.004	0.048	0.296	0.005
dl-Met-Met			0.015	0.003	<0.001	0.305	0.005
quadratic effect4
dl-Met			0.163	0.216	0.061	0.668	0.202
dl-Met-Met			0.445	0.029	0.012	0.277	0.176

¹ Values without the same small letters in the column indicate a significant difference (p < 0.05, n = 8). The data are presented as the mean ± standard error; ² CAT: catalase; T-SOD: total superoxide dismutase; GSH-Px: glutathione peroxidase; T-AOC: total antioxidant capacity; MDA: malonaldehyde; ³ 1: BD; 2: 0.15% dl-Met; 3: 0.30% dl-Met; 4: 0.45% dl-Met; 5: 0.60% dl-Met; 6: 0.15% dl-Met-Met; 7: 0.30% dl-Met-Met; 8: 0.45% dl-Met-Met; 9: 0.60% dl-Met-Met. (BD: basal diet; dl-Met: dl-methionine; dl-Met-Met: dl-methionyl- dl-methionine); ⁴ Trend analysis for BD and BD with 0.15%, 0.30%, 0.45% and 0.60% dl-Met or dl-Met-Met.