Table 7.

TAOC, MDA, CAT, SOD, and GPX activity in the ileal mucosa of broiler chickens fed with oxidized oil and different concentrations of quercetin on day 11.

Item	Treatment1						P-value, t-test	Linear	Quadratic	P-value
	Ctr	Ox	OxL	OxM	OxH	SEM
TAOC2	1.15	0.93	0.97	1.03	0.95	0.034	0.066	0.837	0.306	0.740
MDA3	0.51	0.89∗,a	0.74a,b	0.47c	0.61b,c	0.043	0.008	0.020	0.052	0.021
CAT4	4.49	7.27	8.73	8.05	10.23	0.781	0.128	0.277	0.942	0.690
SOD4	72.37	69.71	68.35	68.31	61.85	2.094	0.662	0.246	0.762	0.677
GPX4	25.28	26.77b	24.89b	24.56b	35.65a	1.417	0.927	0.012	0.218	0.049

∗Means were significantly different compared with the control. Means within 4 treatments (Ox, OxL, OxM, and OxH) lacking a common superscript differ (P < 0.05).

Abbreviations: CAT, catalase; Ctr, control group; GPX, glutathione peroxidase; MDA, malondialdehyde; SOD, superoxide dismutase; TAOC, total antioxidant capacity.

¹Ctr: basal diet; Ox: basal diet with oxidized oil; OxL: basal diet supplemented with oxidized oil and 200 ppm of quercetin; OxM: basal diet supplemented with oxidized oil and 400 ppm of quercetin; OxH: basal diet supplemented with oxidized oil and 800 ppm of quercetin.

²TAOC: U/mg of protein.

³MDA: nM/mg of protein.

⁴CAT, SOD, GPX: U/mg of protein.