大豆素对湘中黑牛育肥牛胴体性能和肉品质的影响

本试验旨在研究饲粮添加大豆素对湘中黑牛育肥牛胴体性能和肉品质的影响。选择14头健康、体重[(450±20)kg]相近、2岁左右阉割湘中黑牛,随机分成2组,每组7头,对照组饲喂基础饲粮,试验组饲喂基础饲粮+500 mg/kg大豆素。试验期为120 d。结果表明:与对照组相比,1)添加大豆素对宰前活重、热胴体重、屠宰率无显著影响(P0.05),胴体的脂肪含量、背膘厚有降低趋势,但差异不显著(P0.05);2)添加大豆素显著提高了背最长肌的粗脂肪含量及大理石花纹评分(P0.05),分别提高了8.34%、1.93分,并显著降低了排酸24 h肌肉的p H和水分含量(P0.05),显著增加了肌肉的红度值(P0.05);3)添加大豆素显著降低了血清中葡萄糖、尿素氮、甘油三酯、总胆固醇、非酯化脂肪酸、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇的浓度(P0.05);4)添加大豆素分别显著提高和降低了背最长肌的异柠檬酸脱氢酶活性和葡萄糖-6-磷酸脱氢酶活性(P0.05)。结果提示,饲粮添加大豆素能够影响育肥牛的脂类代谢,促进肌肉脂肪沉积,改善牛肉的大理石花纹和品质。

Effects of Daidzein on Carcass Performance and Meat Quality of Fattening Xiangzhong Black Cattle

This study was to investigate the effects of dietary supplementation of daidzein on carcass perform-ance and meat quality of Fattening Xiangzhong Black cattle.Fourteen healthy castrated Hunan black cattle aged about 2 years with similar body weight [(450±20) kg] were randomly divided into two groups (n=7).Con-trol group was fed a basal diet while test group was fed the basal diet added 500 mg/kg daidzein.The experi-ment lasted for 120 days.The results showed as follows:compared with control group, 1) the supplementation of daidzein had no significant effects on live weight before slaughter, hot carcass weight and dressing percent-age, and carcass fat content and backfat thickness tended to decrease with an insignificant difference ( P>0.05);2) daidzein supplementation significantly increased ether extract content and marbling score of longissi-mus dorsi by 8.34%and 1.93 ( P<0.05) , respectively, pH after aging for 24 h and moisture content in muscle were significantly reduced ( P<0.05) , and redness value of muscle was significantly increased ( P<0.05);3) daidzein supplementation significantly reduced serum concentrations of glucose, urea nitrogen, triglyceride, to-tal cholesterol, non-esterified fatty acid, high density lipoprotein cholesterol ( HDL-C) and low density lipo-protein cholesterol( LDL-C) ( P<0.05); 4) daidzein supplementation significantly increased and reduced the activities of isocitrate dehydrogenase and glucose 6 phosphate dehydrogenase ( P<0.05) , respectively.The re-sults indicate that dietary supplementation of daidzein can affect fat metabolism, promote intramuscular fat dep-osition, and improve beef marbling and meat quality of fattening cattle.