The experiment was conducted to investigate the effects of maternal dietary supplementation with different sources of selenium (Se) on antioxidant status and mortality of chicken embryo in a model of diquat-induced acute oxidative stress. A total of 180 Meihuang-4 broiler breeders (40wk old) were randomly assigned into three dietary treatments: basal diet (Control), basal diet supplemented with 0.15 mg Se/kg of sodium selenite (SS) or selenomethionine (SM)). Birds were raised for 12 wk. From 10th to 11th week of the experiments, 960 eggs were collected (40 effs per replicate) and assigned into 2 diquat-injected treatments (0 or 25 μg diquat injected on 17th day). There were 3 dietary Se treatments × 2 diquat-injected treatments (CON, SS, SM, CON-DIQ, SS-DIQ, SM-DIQ) in this experiment, each of which was replicated eight times. Then, 240 eggs were slaughtered for analysis on 18th day of hatching, and 720 eggs were used for mortality statistics on 21st day. Results showed that diquat significantly affected chicken embryos mortality and nitric oxide (NO) content, total antioxidation capability (T-AOC), protein carbonyl content, myeloperoxidase (MPO) activity, xanthine oxidase (XOD) activity, total nitric oxide synthase (NOS) activity, monoamine oxidase (MAO) activity and B-cell Leukemia Lynmphoma 2 (bcl-2) content in liver (P < 0.05). Compared with the control, broiler breeders fed with Se had lower reactive oxygen species (ROS) content, NO content, malondialdehyde (MDA) content, protein carbonyl,caspase-3 content and higher T-AOC, glutathione peroxidase (GPx) activity, mitochondrial membrane potential (MMP), MPO activity, XOD activity, MAO activity, bcl-2 content in liver (P < 0.05). There were interactions between dietary Se and diquat in chicken embryo mortality and NO content, CAT activity, MPO activity, MAO activity, caspase-3 content and bcl-2 content (P < 0.05). After diquat-injected, SM-DIQ group had lower chicken embryo mortality, NO content, caspase-3 content, bcl-2 content and higher MPO activity, MAO activity than CON-DIQ group (P < 0.05). Inconclusion, this study indicated that diquat significantly increased free radicals and induced oxidative stress in chicken embryos; maternal dietary supplementation with Se could alleviate the negative effects of diquat in chicken embryos, and SM had better protective effects against oxidative stress induced by diquat than SS.
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