LAUSR

BACKGROUND This study was conducted to investigate the effect of dietary rutin on the meat quality, antioxidant status and mitochondrial structure and function in the breast muscle of heat-stressed broilers. A total of 192 male broilers were randomly assigned into 3 groups and treated with normal control (CON), heat stress (34°C, HS), and heat stress with 500 mg/kg rutin supplementation (HS+Rutin), respectively. RESULTS Dietary rutin significantly increased heat stress-induced decreased body weight, average daily feed intake, average daily gain, and feed efficiency. Rutin supplementation attenuated heat stress-induced impaired meat quality by decreasing the lightness, drip loss at 24 and 48h, the peak time of free water (T22 ) and the peak area ratio of free water (P22 ), and increasing the pH24h and peak area ratio of immobilized water (P21 ). Rutin supplementation promoted superoxide dismutase, glutathione peroxidase activities and total antioxidant capacity, and decreased malondialdehyde levels compared with the HS group. Moreover, rutin attenuated the heat stress-induced mitochondrial damage by increasing the mitochondrial DNA copy number and improving the mitochondrial morphology. Dietary rutin significantly increased mitochondrial biogenesis-related mRNA (PGC-1α, NRF1, and TFAM) expression via the AMPK signaling pathway. Heat stress significantly increased mitophagy-related genes and proteins (Parkin, PINK1, LC3-II) expression, and dietary rutin significantly reversed these alterations. CONCLUSION Dietary rutin attenuated the heat stress-induced declined meat quality and antioxidant capacity of broilers, which may be related to the inhibition of the AMPK/PINK1-Parkin signaling pathway to attenuate mitochondrial damage. This article is protected by copyright. All rights reserved.