不同蛋白水平饲粮对藏羊肌纤维类型转化及肉质特性的影响  

Effect of diets with different protein levels on the transformation of muscle fiber types and meat characteristics of Tibetan sheep

作　　者：吴振岭 周力 张峰硕 曲杨昂毛 季秋蓉 何婷莉 侯生珍[1] 桂林生 WU Zhenling;ZHOU Li;ZHANG Fengshuo;Quyang’angmao;JI Qiurong;HE Tingli;HOU Shengzhen;GUI Linsheng(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810000,Qinghai,China;College of Animal Science and Technology,Ningxia University,Yinchuan 750000,Ningxia,China)

机构地区：[1]青海大学农牧学院,青海西宁810000 [2]宁夏大学动物科技学院,宁夏银川750000

出　　处：《草业科学》2024年第5期1210-1220,共11页Pratacultural Science

基　　金：青海省科技厅帅才科学家项目(2022NK169)。

摘　　要：选取体重(15.40±0.81)kg相近的2月龄高原型藏羔羊90只,随机将其分为3个处理组,每处理组各30只,分别饲喂蛋白水平为10.20%(L组)、11.58%(M组)和13.03%(H组)的饲粮,研究不同蛋白水平饲粮对藏羊肉品质及肌纤维组织学特性的影响。结果显示:10.20%蛋白组中藏羊肌肉抗氧化能力、谷胱甘肽过氧化物酶、过氧化氢酶和超氧化物歧化酶活性显著低于11.58%蛋白组(P<0.05)。M组肌肉弹性显著高于13.03%蛋白组和11.58%蛋白组(P<0.05),11.58%蛋白组肌肉咀嚼性和胶着性显著低于10.20%蛋白组和13.03%蛋白组(P<0.05);13.03%蛋白组中Ⅰ、Ⅱa和Ⅱb型肌纤维直径显著大于10.20%蛋白组(P<0.05),11.58%蛋白组中Ⅰ、Ⅱa和Ⅱb型肌纤维密度显著高于13.03%蛋白组(P<0.05);11.58%蛋白组氧化型肌纤维数量、面积比例显著高于10.20%蛋白组(P<0.05);10.20%蛋白组MyHCⅠ表达量显著高于11.58%蛋白组与13.03%蛋白组,11.58%组MyHCⅡa表达量显著高于10.20%蛋白组,10.20%蛋白组MyHCⅡb表达量显著高于11.58%蛋白组与13.03%蛋白组(P<0.05)。MyHCⅠ、MyHCⅡa基因表达量与咀嚼性显著负相关(P<0.05)。MyHCⅡ基因表达量与总抗氧化能力显著负相关(P<0.05),与咀嚼性与硬度显著正相关(P<0.05)。综上,本试验中,当饲粮中蛋白水平为11.58%时,可改善藏羊背最长肌肌纤维特性,加强肌纤维从酵解型肌纤维向氧化性转化,提高氧化型面积比例,从而利于改善肉品质。This experiment aimed to study the effects of different protein level rations on meat quality and histological characteristics of muscle fibers in Tibetan lambs.Ninety two-month-old plateau-type Tibetan lambs weighing(15.40±0.81 kg)were selected and randomly divided into three treatment groups of 30 lambs each,and fed diets with protein levels of 10.20%(group L),11.58%(group M),and 13.03%(group H).The diets were fed to the animals at the same time.The results showed that the antioxidant capacity(T-AOC),glutathione peroxidase(GSH-Px),catalase(CAT),and superoxide dismutase(SOD)activity levels of Tibetan sheep muscles in group L were significantly lower than those in group M(P<0.05).The elasticity of the muscles in group M was significantly higher than that of the muscles in groups H and M(P<0.05);muscle chewiness and adhesion were significantly lower in group M than in groups L and H(P<0.05);the diameter of the type-Ⅰ,Ⅱa,andⅡb muscle fibers was significantly greater in group H than in group L(P<0.05),and the diameter of the type-Ⅰ,Ⅱa,andⅡb muscle fibers was significantly greater in group M than in group L(P<0.05);the densities of the type-Ⅰ,Ⅱa,andⅡb muscle fibers in group M were significantly higher than in group H(P<0.05);the number and area ratio of oxidized muscle fibers were significantly higher in group M than in group L(P<0.05);the expression level of MyHCⅠwas significantly higher in group L than in group M vs.group H;the MyHC IIa expression level in group M was significantly higher than in group L,and the MyHC IIb expression level in group L was significantly higher than in groups M and H(P<0.05).The gene expression levels of MyHC I and MyHC IIa were significantly negatively correlated with masticatory property(P<0.05).The gene expression level of MyHC II significantly correlated with T-AOC(P<0.05).Gene expression was significantly negatively correlated with T-AOC(P<0.05)and significantly positively correlated with chewability and hardness(P<0.05).In conclusion,in this experiment,a prote

关 键 词：蛋白水平 高原型藏羊 抗氧化能力 质构品质 肌纤维类型 MyHCs基因 

分 类 号：S82[农业科学—畜牧学]