【作者】 胥蕾；

【导师】 齐广海；

【作者基本信息】 中国农业科学院 ， 动物营养与饲料科学， 2011， 博士

【摘要】 本论文对当前市场上最常见的两种致晕类型——电致晕和气致晕进行了研究。全文分6个试验,采用分光光度、放射性免疫、冰冻切片、免疫组化、反相高效液相色潽、电子自旋共振波谱（ESR）、实时荧光定量PCR等方法系统研究了致晕方法对肉仔鸡肉品质的影响并初步探讨了其营养调控机制。论文首先研究了不同电、气致晕参数对肉仔鸡肉品质的影响,在此基础上,对两种致晕方法作了参数优化;然后,从能量代谢和脂质过氧化代谢的角度对电致晕和气致晕方法的影响进行了对比;接着,分别研究了MAPK-Nrf2/ECH-ARE信号转导通路对活性氧的产生和消除的作用,探讨了致晕方法影响肌肉脂质过氧化的深层机制;最后,通过在肉仔鸡日粮中添加抗氧化剂维生素E（VE）,研究了VE对致晕造成的脂质过氧化损伤的缓解作用,并从MAPK-Nrf2/ECH-ARE信号转导通路的角度探讨了VE调节肌肉抗氧化能力的机制。试验一旨在探究电流参数（低电流和高频率）对肉仔鸡肉品质、糖酵解潜能和血液指标的影响。研究了35 V, 46 mA;50 V, 67 mA;和65 V, 86 mA与160 Hz, 400 Hz,和1,000 Hz的9种组合方式。54只肉仔鸡在被电流致晕18秒后采用颈部放血屠宰。屠宰后45分钟和24小时之内取胸肌和大腿肌肉测定肉品质,取胫骨前肌肉测定糖酵解潜能。试验表明,总体上高频率降低了胸肌中的剪切力(400 Hz和1,000 Hz vs. 160 Hz,以及腿肌中的烹煮损失（1,000 Hz vs. 160 Hz和400 Hz） （P < 0.01）。当电流较高时（50 V, 67 mA,,65 V, 86 mA）高频率（400 Hz和1,000 Hz）有降低胸肌中的剪切力的效果（P < 0.01）;但当电流强度较低时（35 V, 47 mA）高频率（1,000 Hz）导致剪切力增加（P < 0.01）。1,000 Hz （vs. 160 Hz）降低了胸肌中糖原和糖酵解潜能（P < 0.05）。较高的致晕电流（≥50 V, 67 mA）降低了血浆皮质酮的水平（P < 0.05）,但频率对血浆皮质酮的影响不显著。电流强度和频率互作影响了血浆葡萄糖、胸肌24h红度值、剪切力,腿肌的极限pH,以及腿肌的糖酵解潜能。本研究表明,在电流强度不太低（50 V, 67 mA以上）的情况下采用高频率（400和1,000 Hz）致晕具有改善肉品质的作用。试验二旨在探讨不同浓度的二氧化碳对肉仔鸡血液指标、糖酵解潜能,和热剔骨后肉品质的影响。总共30只肉仔鸡分别分配到5个处理:40% CO₂ + 30% O₂ + N₂ （对照组）;30% CO₂ +21%O₂ + N₂ （G30%）;40% CO₂ + 21% O₂ + N₂ （G40%）;50% CO₂ + 21% O₂ + N₂ （G50%）;60% CO₂ + 21% O₂ + N₂ （G60%）。屠宰后后45分钟和24小时之内取胸肌和腿肌测定测定肉品质及糖酵解潜能。试验表明,60%的二氧化碳致晕导致胸肌（vs. G30%和G40%）和腿肌（vs. G40%）中的极限PH降低（P < 0.05）,胸肌的（vs. G30%）滴水损失率增加（P = 0.01）。50%二氧化碳导致腿肌的滴水损失率高于30%组,并且屠宰后24h的胸肌比30%和40%二氧化碳致晕组更苍白（亮度值更高）（P < 0.01）。与对照相比,40%二氧化碳有降低腿肌24h苍白度的趋势（P < 0.10）。G30%和G40%导致胸肌糖酵解潜能低于G60%,而腿肌中的糖酵解潜能在G30%最低（P < 0.01）。血浆皮质酮、血浆葡萄糖、宰后45min的肉品质（pH、亮度、红度,黄度）不受二氧化碳水平的影响（P > 0.05）。本研究表明,低浓度二氧化碳（30%, 40%）具有提高肉品质的作用,但与较高浓度的二氧化碳相比对缓解动物应激没有优势。试验三比较了高碳酸血正常氧浓度的气致晕和低电流、高频率电致晕对屠宰后肌肉糖代谢和能量代谢的影响。总共对36只肉仔鸡施以6个处理:不致晕直接宰杀（对照组）;40% CO₂ + 21% O₂ + N₂ （G40%）;60% CO₂ + 21% O₂ + N₂ （G60%）;35 V, 47 mA,400 Hz （E35V）;50 V, 67 mA, 160 Hz（E50V）; 65 V, 86 mA, 1000 Hz （E65V）。屠宰后45分钟内取胸肌和胫骨前肌储存于?80℃。试验表明,与电致晕和对照组相比,所有气致晕组都造成全血pH值降低（P < 0.01）。电致晕和气致晕对血浆指标、糖酵解潜能、磷酸腺苷、纤维密度没有显著影响。与对照相比,G40%和E35V造成血浆乳酸含量增加,E35V还造成血浆尿素氮和尿酸增加（P < 0.05）; E35V和E50V降低了IIB型纤维的密度（P < 0.05）;G60%导致胸肌中GP增加,而除了E50V之外的所有致晕处理都导致腿肌中的GP降低（P < 0.01）。与较高的电流强度（E50V和E65V）相比,G40%降低了胸肌中的能量水平（ATP降低,AMP和AMP/ATP升高, P < 0.05）。但是,气致晕和较低电流强度（E35V）的电致晕相比,无论胸肌还是腿肌中磷酸腺苷的水平都没有显著差异。本研究表明,采用低电流强度、高频率的电致晕与采用高碳酸血正常氧浓度的气致晕相比,肉仔鸡肌肉的糖代谢和能量代谢没有本质区别。从能量代谢的角度来看,G40%是较优的致晕参数组合。试验四对高碳酸血正常氧浓度气体致晕和低电流、高频率的致晕对屠宰后肌肉脂质过氧化的影响做了比较,并通过血液指标、肌肉活性氧（ROS）和硫代巴比妥酸反应产物浓度、肌肉纤维类型比例以及家禽解耦联蛋白（avUCP）、家禽腺苷转位因子（avANT）、过氧化物酶体增殖物激活受体γ辅激活因子1α（avPGC-1α）的mRNA水平探讨了可能的作用机制。总共将36只鸡给以6种处理:不致晕（对照）;40% CO₂ + 21% O₂ + N₂ （G40%）; 60% CO₂ + 21% O₂ + N₂ （G60%）;35 V, 47 mA, 400 Hz （E35V）;50 V, 67 mA, 160 Hz （E50V）;65 V, 86 mA, 1000 Hz （E65V）。气致晕导致屠宰后45min腿肌中活性氧水平和胸肌中TBARS水平降低。但是宰后24h胸肌和腿肌中TBARS含量不受致晕类型的影响。与电致晕相比,气致晕诱导avUCP mRNA （胸肌1.47倍,腿肌2.41倍）和avPGC-1αmRNA （胸肌1.42倍,腿肌2.08倍）表达量上升。本研究表明,与低电流+高频率的电致晕相比,高碳酸血正常氧浓度气致晕通过上调avUCP和avPGC-1α使屠宰后45min的活性氧产量和脂质过氧化程度降低,但是24h后不同致晕类型对脂质过氧化没有显著影响。试验五从抗氧化酶（SOD）、二相酶（GST）和调控它们表达的MAPK-Nrf2/ECH-ARE信号转导通路的角度着手,研究了不同致晕方法对肉仔鸡肌肉在储存期间肉色和脂质氧化的影响及脂质过氧化物清除的机制。对共计30只AA肉仔鸡分别施以5种处理:不致晕（对照）,G40% = 40% CO₂ + 21% O₂ + N₂;G79% = 79% CO₂ + 21% O₂;E65V = 65 V,86 mA,1000 Hz;E150V =150 V,130 mA,60 Hz。试验结果表明,与对照组相比,E65V导致血清尿酸升高。在屠宰后9天胸肌中G40%亮度（L*,表明苍白）最低,E150V亮度最高（P < 0.01）;屠宰后6天和9天G79%和E150V导致胸肌褪色程度最高（P < 0.05）。在致晕处理的胸肌中,G40%导致在屠宰后的45min、3天、6天、9天的TBARS处于最高水平,而E150V导致屠宰后各个时间点都处于较低的水平（P < 0.01）。在腿肌中,G40%致晕导致屠宰后1天的TBARS有高于其它致晕处理的趋势（P < 0. 10）,并且屠宰后6天的TBARS含量高于E65V（P < 0.01）。在致晕处理组中,屠宰后45 min G40%的胸肌SOD活性有高于E65V的趋势（P = 0.07）,气致晕两个处理的GST活性均高于两个电致晕组（P < 0.01）。胸肌冷藏1天后G40%的SOD活性高于其它致晕组（P < 0.01）,G40%和E150V的GST活性高于E65V（P < 0.01）。屠宰后1d G40%和G79%分别导致腿肌中的SOD和GST活性高于对照组。此外,G40%不仅抑制了胸肌和腿肌MAPK通路蛋白（ERK1/2, JNK1, JNK2, p38）的表达,而且抑制了胸肌中各种抗氧化基因（SOD1、SOD2、GSTA3、GSTK1、GSTM2、GSTT1）的表达。与G40%相反,E65V不仅上调了胸肌和腿肌所有MAPK通路蛋白的表达,而且还上调了除SOD2之外的所有腿肌抗氧化基因的表达,表明G40%和E65V分别对该通路产生了抑制和激活刺激。G79%和E150V对MAPK通路和抗氧化基因表达的影响介于G40%和E150V之间。在致晕处理中,G40%和E65V都有维护储存期内肉色稳定的效果。其中E65V通过升高血清尿酸水平、激活MAPK信号通路及该通路下游的SOD和GST的基因表达,增强了抗氧化能力,缓解了肉品在储存期间的脂质过氧化。与此相反,G40%由于屠宰初期对上述基因的表达发生抑制,显示适应性较低,肉品在储存期间受到更强的氧化损伤。试验六旨在研究屠宰前不同阶段在肉仔鸡日粮中添加200 mg/kg DL-α-生育酚乙酸酯（VE）对高电流低频率电致晕屠宰后的肉仔鸡骨骼肌脂质过氧化的影响,并通过对MAPK-Nrf2/ECH-ARE信号通路的研究,探讨VE缓解致晕造成的氧化应激的作用机理。试验分为4个处理,每个处理6个重复,每个重复10只鸡。艾拔益加（AA）肉仔鸡在0～17日龄统一采食含正常VE浓度（20 mg/kgα-生育酚乙酸酯）的基础日粮。在饲养后期（18～38日龄）配制饲喂基础日粮VEb（无额外添加VE）和处理日粮VEc（添加200 mg/kgα-生育酚乙酸酯）。对照组在18～38日龄只采食VEb;VE1w组在18～31日龄采食VEb,在32～38日龄采食VEc;VE2w组在18～24日龄采食VEb,在25～38日龄采食VEc;VE3w组在18～38日龄一直采食VEc。饲养至38日龄时,每个重复取1只鸡,用150V,130 mA致电致晕1秒。取胸大肌和髂腓肌测定各项肌肉的指标。结果表明,日粮中添加VE 1～3周导致屠宰后45 min、2天、6天胸肌中TBARS和致屠宰后45 min、2、4、6天腿肌中TBARS含量降低（P < 0.01）。屠宰后2天,腿肌中TBARS含量表现为不添加VE>添加VE3周>添加VE2周>添加VE1周（P < 0.01）。添加VE的所有处理组导致VE在胸肌和腿肌中的沉积量上升。在VE添加组中,VE在胸肌和腿肌中的沉积量多少的顺序为添加3周< 2周< 1周（P < 0.01）。与对照相比,添加VE 1～2周下调了胸肌中MAPK-Nrf2/ECH-ARE通路中JNK1,JNK2和ECH （鸡的Nrf2）的表达,添加3周上调了JNK1,JNK2和ECH的表达。与对照相比,添加1周下调了腿肌中JNK1,JNK2,p38和ECH的表达,与添加1周效果相反,添加2周上调了腿肌中JNK1,JNK2,p38和ECH的表达;添加3周只上调了JNK1和ECH的表达。与对照相比,添加VE1周导致屠宰后45 min腿肌中GST活性降低（P < 0.01）,添加VE 1～2周导致屠宰后2天腿肌GST活性增加（P < 0.01）。本试验揭示,添加200 mg/kg VE 1周通过增加VE在肌肉中的沉积起到减小了宰前应激对MAPK-Nrf2/ECH-ARE氧化应激通路的刺激、增强了骨骼肌对脂质过氧化的抵抗作用。更多还原

【Abstract】 The most widely used stunning methods （electrical stunning and gas stunning） were studied using 6 experiments. The effect of stunning methods on meat quality was systematically studied and nutritional modulation of lipid peroxidation was approached in broiler chicks by using the methods of absorption spectrometry, radiation immune assay, reversed-phase high-performance liquid chromatograph （RP-HPLC）, electron spin resonance spectroscopy （ESR）, real time quantitative RT-PCR （Reverse transcription-PCR）. Firstly, the effects of different electrical and gas stunning parameters on meat quality were studied, and the parameters were optimized. Then, comparisons were done on the energy metabolism and lipid peroxidation in skeletal muscles between broilers stunned with electricity and gas mixtures. The possible mechanisms were further investigated through the studies on mitochondrial uncoupling proteins and MAPK-Nrf2/ECH-ARE signal transduction pathway. Eventually, Vitamin E （200 mg/kg DL-α- tocopherol） was supplemented in the diet to alleviate the oxidative damage in muscles from high-current-stunned broilers. The effect of VE on MAPK-Nrf2/ECH-ARE signal transduction pathway was also studied. Abstracts for experiments were listed as follows.Experiment 1 was designed to determine the effect of electrical stunning （ES） variables （low currents and high frequencies） on meat quality, glycolytic potential, and blood parameters in broilers. A total of 54 broilers were stunned with nine ES methods for 18 s, using sinusoidal alternating currents combining 35 V, 47 mA, 50 V, 67 mA, and 65 V, 86 mA with 160 Hz, 400 Hz, and 1,000 Hz. Samples for meat quality were obtained from the pectoralis major （PM） and musculus iliofibularis （MI）, and samples for glycogen metabolism were taken from PM and tibialis anterior （TA） muscle at 45 min postmortem. The use of high frequency reduced the shear value in PM （400 Hz and 1,000 Hz vs. 160 Hz, P < 0.01）, and cooking loss in MI （1,000 Hz vs. 160 Hz and 400 Hz, P < 0.01）. The shear value of PM decreased at high frequency （400 Hz and 1,000 Hz） when current was high （50 V, 67 mA, and 65 V, 86 mA, P < 0.01）, but increased at high frequency （1,000 Hz） when current was low （35 V, 47 mA）. Stunning with 1,000 Hz （vs. 160 Hz） caused low glycogen, and glycolytic potential （GP） in PM （P < 0.05）. Plasma corticosterone decreased （P < 0.05） at high currents （≥50 V, 67 mA）, but was not affected by changes in frequency. Electrical current interacted with frequency in plasma glucose, a* 24h, shear value （PM）, ultimate pH （MI） and GP （TA） （P < 0.05）. This study indicated that high stunning frequencies （400 and 1,000 Hz） may potentially improve meat quality without aggregating stress when the current was not too low （more than 50 V, 67 mA）.Experiment 2 was aimed to investigate the effects of different carbon dioxide （CO₂） concentrations on blood variables, glycolytic potential （GP）, and meat quality of hot-boned muscles in broilers. Thirty broilers were exposed to one of the following five gas mixtures for 90 s: 40% CO₂ + 30% O₂ + N₂ （Control）; 30% CO₂ +21%O₂ + N₂ （G30%）; 40% CO₂ + 21% O₂ + N₂ （G40%）; 50% CO₂ + 21% O₂ + N₂ （G50%）; 60% CO₂ + 21% O₂ + N₂ （G60%）. Samples were taken from the pectoralis major （PM）, musculus iliofibularis （MI）, and tibialis anterior muscles （TA） 45 min postmortem. The ultimate pH in both the PM （vs. G30% and G40%） and MI （vs. G40%, P < 0.05） was decreased with G60%, whereas drip loss in the PM （vs. G30%, P < 0.01） was increased with G60%. Drip loss in the MI （vs. control and G30%, P < 0.01） was increased with G50%. Lightness after 24 h （L*24h） in PM （vs. 30% and 40%, P < 0.01） was increased in group G50%. In MI muscle, L*24h was slightly decreased with G40% compared with the control （P < 0.10）. The GP value in the PM was lower in the G30% and G40% than those in G60% （P < 0.05）, and the GP value in the TA was the lowest in the G30% （P < 0.01）. Plasma corticosterone, plasma glucose and meat quality （pH, redness, yellowness） 45 min postmortem were not affected by CO₂ levels （P > 0.05）. In conclusion, stunning broilers with low CO₂ levels （30%, 40%） improved meat quality, but had no advantage in alleviating animal stress as compared with high CO₂ levels （50%, 60%）.Experiment 3 was aimed to compare the effects of gas stunning （GS） and electrical stunning （ES） on energy metabolism in Arbor Acres broilers. Thirty-six birds were slaughtered without stunning （control） or after stunning with the following treatments: 40% CO₂ + 21% O₂ + N₂ （G40%）;60% CO₂ + 21% O₂ + N₂ （G60%）, 35 V, 47 mA, 400 Hz （E35V）, 50 V, 67 mA, 160 Hz （E50V）, and 65 V, 86 mA, 1,000 Hz （E65V）. Muscle samples were obtained from the pectoralis major （PM） and tibialis anterior （TA） muscles 45 min postmortem and stored at ?80℃. Blood pH was decreased consistently with GS （G40% and G60%） compared with ES and the control （P < 0.01）. No consistent differences were observed between GS and ES in the plasma variables, glycolytic potential （GP）, adenosine phosphates, or fiber intensities. Plasma lactate was increased with G40% and E35V （P < 0.05）, whereas plasma uric acid and urea nitrogen were increased with E35V （P < 0.05） as compared with the control. Compared with the control, the intensity of type IIB fibers decreased in broilers stunned with E35V and E50V （P < 0.05）; and GP was increased （P < 0.01） with G60% in the breast muscle and reduced （P < 0.01） in the leg muscle with all the stunning treatments except for E50V. Energy was decreased （lower ATP, higher AMP and AMP to ATP ratio, P < 0.05） in breast muscle with G40% compared with ES at high currents （E50V and E65V）. However, the adenosine phosphates with GS were not significantly different （P > 0.05） from ES at low current （E35V） either in breast or leg muscle. In conclusion, there was no essential difference in energy metabolism in broilers stunned with ES and GS, when ES was based on low current and high frequency and GS was based on hypercapnic hypercapnic moderate oxygenation stunning. The G40% is potentially a superior stunning variable among treatments from the view of energy metabolism.Experiment 4 was aimed to compare the effects of stunning methods （electrical stunning, ES vs. gas stunning, GS） on lipid peroxidation in broiler meat, and investigate possible mechanism through measuring plasma variables, muscle reactive oxygen species （ROS） and thiobarbituric acid reactive substances （TBARS） concentrations, muscle fiber ratios, and mRNA levels of avian uncoupling protein （avUCP）, avian adenine nucleotide translocator （avANT）, and avian peroxisome proliferator-activated receptor-γcoactivator-1α（avPGC-1α）. Arbor Acres broilers （AA, n = 36） were not stunned （control） or exposed to the following stunning treatments: 40% CO₂ + 21% O₂ + N₂ （G40%）;60% CO₂ + 21% O₂ + N₂ （G60%）; 35 V, 47 mA, 400 Hz （E35V）, 50 V, 67 mA, 160 Hz （E50V）, and 65 V, 86 mA, 1,000 Hz （E65V）. The ROS level in tibialis anterior （TA） （P < 0.05） and the TBARS concentration in pectoralis major （PM） （P < 0.001） were decreased with GS groups compared with ES groups at 45 min postmortem. However, the TBARS concentrations 24 h postmortem in PM or TA were not affected by stunning methods （ES and GS）. Compared with ES groups, the GS caused a higher expression of avUCP mRNA （1.47 fold in PM, and 2.41 fold in TA） and avPGC-1αmRNA （1.42 in PM and 2.08 fold in TA）. In conclusion, the up-regulation of avUCP and avPGC-1αreduced the ROS accumulation and lipid peroxidation at 45 min postmortem in skeletal muscles of hypercapnic normal oxgenation gas stunned broilers. However, these changes were not sufficient to cause difference in the meat lipid peroxidation 24 h postmortem between hypercapnic moderate oxgenation GS and low current and high frequency ES.Experiment 5 was aimed to study the effect of stunning methods on meat color and lipid peroxidation, and explored the mechanism of peroxide scavenging through MAPK signaling pathway and its downstream SOD, GST expression in broilers. Totally 30 AA broilers were exposed to no stunning （control） or the following stunning treatments: 40% CO₂ + 21% O₂ + N₂ （G40%）; G79% = 79% CO₂ + 21% O₂;E65V = 65 V,86 mA,1000 Hz;E150V =150 V,130 mA,60 Hz. Compared with the control, uric acid was increased in E65V, and meat discoloration was increased in G79% and E150V at 6 and 9 days postmortem（P < 0.05）.Among the stunning treatments at 9 days postmortem, lightness （L*） was the lowest in G40%, and the highest in E150V （P < 0.01）. In the breasts among the stunning treatments, the TBARS 45min, 3d, 6d, 9d levels were the highest with G40%, whereas the TBARS levels remained at low levels with E150V during the storage （P < 0.01）. In the thigh, the TBARS 1d （P < 0. 10） and 6d （P < 0.01） concentrations were higher in G40% compared with E65V. In the thighs among the stunning groups, the activity of SOD 45min tended to be higher with G40% than that with E65V （P = 0.07）, and the activity of GST 45min was higher than with the electrical stunning groups （P < 0.01）; the activity of SOD 1d was increased in G40% compared with other stunning groups, and the activity of GST 1d was increased with G40% and E150V compared with E65V （P < 0.01）. The activity of SOD 1d （P=0.03） and GST 1d （P=0.08） in thighs was increased respectively with G40% and G79% compared with the control.The G40% suppressed the transcriptional expressions of MAPK pathway （ERK1/2, JNK1, JNK2, p38） and its downstream antioxidant enzyme and Phase II enzymes （SOD1、SOD2、GSTA3、GSTK1、GSTM2、GSTT1） in breast . To the contrast, E65V up-regulated the expression of all the genes of MAPK pathway in breast and thigh muscles, and genes of antioxidant enzyme and Phase II enzymes excepted for SOD2 in thigh. Results showed that the MAPK-Nrf2/ECH-ARE pathway was suppressed by G40%, whereas activated by E65V.The level of G79% and E150V on MAPK pathway and antioxidant genes were among the treatments G40% and E150V. Overall, the MAPK pathway was mainly suppressed by GS （especially low CO₂ concentration）, whereas, mainly activated by ES （especially low current + high frequency）. The meat color was well maintained by both G40% and E65V. The E65V increased serum uric acid, activated the expression of MAPK-Nrf2/ECH-ARE pathway genes and its downstream SOD and GST genes, showing a good adaptation reaction to slaughter stress, thus caused an increase in the antioxidant ability and delayed meat lipid peroxidation thereafter. However, G40% suppressed the antioxidant genes and MAPK pathway, showing a poor adaptation reaction, and led to higher meat oxidation during prolonged meat storage.Experiment 6 was aimed to study the effect of dietary VE on meat lipid peroxidation induced by high current/low frequency electrical stunning （ES） in broilers, and explored the molecular mechanism through MAPK-Nrf2/ECH-ARE signaling pathway. Totally 240 1-day-old AA broilers were distributed to 4 treatments, with 6 replicates in each treatment, and 10 broilers per replicate. Broilers were fed with normal diet （20 mg/kg DL-α- tocopherol, VEa） in the first stage （days 0～17）. A basal diet （no supplementation ofα- tocopherol, VEb） and treatment diet （200 mg/kg DL-α- tocopherol, VEc） were prepared for the second stage （days 18～38）. The control birds were fed with VEb through days 18～38; Birds from treatments VE1w, VE2w, VE3w were firstly fed with VEb, and then with the diet VEc （200 mg/kgα- tocopherol） respectively since day 32, 25, and 18. On day 38, one bird per replicate was selected （body weight 2.0±0.2）, stunned with an alternative current of 150V, 130 mA, 60Hz, for 1s. Pectoralis major （PM, breast） and musculus iliofibularis （MI, thigh） were taken for measurements. TBARS concentrations were decreased in breast （45min, 2d, 6d postmortem） and thigh （45min, 2d, 4d, 6d postmortem） muscles with VE groups （VE1w, VE2w, VE3w, P < 0.01）. The TBARS concentration order was that control > VE3w > VE2w > VE1w in thigh at 2d postmortem （P < 0.01）. Compared with the control, the precipitation of VE was increased in breast and thigh muscles with VE supplementation groups, with the order of VE1w > VE2w > VE3w > control （P < 0.01）. Compared with the control in breast, the gene expressions of JNK1, JNK2 and ECH （chicken Nrf2） in the MAPK-Nrf2/ECH-ARE pathway was decreased by VE1w and VE2w, whereas the expression of JNK1, JNK2 and ECH was increased in VE3w. Compared with the control in thigh, JNK1, JNK2, p38 and ECH were down-regulated by VE1w, while up-regulated by VE2w. The JNK1 and ECH were up-regulated by VE3w in thigh. The activity of SOD and GST in breast was not affected by VE supplementation （P > 0.05）. Compared with the thigh of control, activity of GST 45min was decreased with VE1w （P < 0.01）, and the activity of GST 2d was increased with VE1w and VE2w （P < 0.01）. Conclusion, a VE supplementation for 1 week caused the highest VE level in muscles, which decreased the slaughter stress, suppressed the MAPK-Nrf2/ECH-ARE oxidative stress signaling, alleviated the oxidative stress and meat oxidation in broilers.更多还原