Effects of early weaning on the concentration of antioxidant status ([A] MDA, [B] GSH-Px, [C] T-SOD, [D] T-AOC, and [E] CAT) of duodenum content of 25-day-old squabs in two groups. CON group: control group; EW group: test group, squabs were fed by parental pigeons for first 6 d after hatching, and then fed by hand. Values means n = 8 for the analysis of the intestine form. Data are means ± SEM. * means P < 0.05; ** means P < 0.01.