Effects of Short-Term Feeding of Resveratrol on Growth Performance, Meat Quality, Antioxidant Capacity, Serum Biochemical Parameters and Intestinal Health in Yellow-Feathered Broilers Under Dexamethasone-Induced Oxidative Stress

Oxidative stress is believed to deteriorate production performance and cause substantial economic losses in commercial poultry farming. Resveratrol (RES) is a polyphenolic antioxidant that can improve intestinal barrier function and regulate gut microbiota composition. This study aimed to evaluate whether short-term (14 days) dietary resveratrol (1000-3000 mg/kg) mitigates dexamethasone (DEX)-induced oxidative stress and performance loss in yellow-feathered broilers. Two hundred and forty 52-day-old birds were assigned to five treatments (<i>n</i> = 8 pens × 6). Control (CON) and DEX groups received the basal diet; DR1, DR2 and DR3 were provided with the basal diet plus 1000, 2000 or 3000 mg/kg RES. During days 1-5, the DEX and RES (DR1, DR2 and DR3) groups were intraperitoneally injected with 5 mg/kg BW DEX; CON birds received saline. DEX significantly reduced average daily gain (ADG) and raised feed conversion ratio (FCR) (<i>p</i> < 0.05) without altering feed intake. RES at 1000-2000 mg/kg improved ADG, reduced FCR and lowered serum corticosterone and blood urea nitrogen while increasing albumin (<i>p</i> < 0.05). DEX elevated malondialdehyde (MDA) in liver and thigh muscle, suppressed liver catalase (CAT) activity, and suppressed thigh muscle superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and CAT activities. In serum, only SOD activity decreased. RES partially alleviated the abnormal changes in these antioxidant indices. Intestinally, DEX increased MDA, shortened villi and reduced the villus-to-crypt ratio, whereas RES partially reinstated ileal morphology, decreased MDA dose-dependently and linearly enhanced duodenal SOD activity (<i>p</i> < 0.05). DEX downregulated Occludin mRNA; RES upregulated Occludin and elevated ileal GPX2, SOD, CAT and PPAR-γ transcripts with a quadratic response to RES dose, while lowering duodenal CAT mRNA. Overall, short-term RES supplementation-particularly at 1000-2000 mg/kg-improves growth performance, meat quality and intestinal health of yellow-feathered broilers under DEX-induced oxidative stress by enhancing systemic and intestinal antioxidant capacity and reinforcing epithelial barrier integrity.