Abstract
To investigate the etiopathogenesis of fatty liver hemorrhagic syndrome (FLHS) and the protective effects of resveratrol (RSV) against FLHS in laying hens, 144 healthy 90-day-old laying hens were randomly divided into 4 groups including control (Con) group, high-energy low-protein (HELP) group, RSV group, and HELP + RSV group, each of which contained 36 hens with 3 replicates. Birds in the 4 groups were fed a basal diet, HELP diet, basal diet supplemented with 400 mg/kg RSV, and HELP diet supplemented with 400 mg/kg RSV. The histopathology of the ovary lesions on day 120, egg production, antioxidative function, and mRNA expression levels of inflammatory cytokines on days 40, 80, and 120 were determined. The lipid accumulation and hemorrhaging were more severe in the HELP group than those in the HELP + RSV group. The laying rate was markedly decreased in the HELP group compared with that in the Con and HELP + RSV groups. Furthermore, the malondialdehyde concentration was significantly increased (P < 0.05), while the levels of superoxide dismutase (SOD), catalase, and glutathione were significantly decreased (P < 0.05) in the HELP group compared with those in the Con and HELP + RSV groups. The mRNA levels of antioxidant genes (Nrf2, SOD-1, and HO-1) were markedly increased (P < 0.05) in the HELP + RSV group compared with those in the HELP group. In addition, the mRNA levels of inflammation-related genes (nuclear factor kappa B, tumor necrosis factor-α, IL-1β, and IL-6) were significantly increased (P < 0.05) in the HELP group compared with those in the Con and HELP + RSV groups. Collectively, these results indicate that oxidative stress and inflammation are involved in the occurrence and development of FLHS in the ovaries of laying hens, but RSV effectively attenuates oxidative stress and inflammation in hens with FLHS. Hence, RSV can be used as an effective feed additive to protect against FLHS.