Effects of different levels of rutin on growth performance, immunity, intestinal barrier and antioxidant capacity of broilers. Issue 1 (31st December 2022) - Chen, Shun
Abstract: This study investigated the effects of different doses of rutin on the growth performance, immunity, intestinal barrier, and antioxidant capacity of broilers. A total of two hundred and fifty-six 1-day-old male broilers were divided into 4 groups and fed basal diets supplemented with 0 (control group), 250, 500 and 1, 000 mg rutin/kg, respectively, for 42 days. In the starter period (days 1–21) and whole trial period (days 1–42), broilers fed diets containing 500 mg rutin/kg had significantly ( p < 0.05) higher average daily feed intake, body weight and average daily gain and better feed conversion ratio. Dietary 500 mg rutin/kg increased the villus height, villus height to crypt depth ratio and villus area, while reducing the B cell lymphoma 2 associated X mRNA expression ( p < 0.05). Dietary 500 mg rutin/kg increased the level of IgA in serum and decreased serum tumour necrosis factor-α (TNF-α) content, and the nuclear factor kappa-B, interleukin-2 and TNF-α mRNA expression in jejunal mucosa ( p < 0.05). Simultaneously, 500 and 1, 000 mg rutin/kg significantly decreased serum diamine oxidase activity, D-lactic acid and lipopolysaccharide concentration, increased activities of total superoxide dismutase and total antioxidant capacity in jejunal mucosa ( p < 0.05), and upregulated mRNA expressions of genes related to intestinal barrier and antioxidant capacity in jejunal mucosa ( p < 0.05). These findings indicate that dietary rutin, especially at 500 mg/kg, improves broilers' growth performance, intestinal barrier function, immunity, and antioxidant capability, which may be related to the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway. Highlights: Dietary rutin improved growth performance, jejunal morphology, and intestinal barrier function. Dietary rutin enhanced the immunity via inhibiting NF-κB, and improved antioxidant capacity via activating Nrf2/HO-1 pathway in broilers. The optimal dose of rutin was 500 mg/kg in broiler diet.