幼龄和成年牦牛肌纤维类型、MyHC基因表达及其肌肉抗氧化能力的比较研究  

Comparative Study on Muscle Fiber Types,MyHC Gene Expression and Antioxidant Capacity of Yak at Different Developmental Stages

作　　者：周力 姚有莉 李蒋伟 马博妍 高占红 桂林生 ZHOU Li;YAO YouLi;LI Jiangwei;MA Boyan;GAO Zhanhong;GUI Linsheng(College of Agriculture and Animal Husbandry,Qinghai University,Xining 810016,China)

机构地区：[1]青海大学农牧学院,西宁810016

出　　处：《四川农业大学学报》2021年第2期254-259,共6页Journal of Sichuan Agricultural University

基　　金：国家自然科学基金项目(31960649)。

摘　　要：【目的】研究幼龄和成年牦牛肌肉抗氧化能力和肌纤维组织学特性。【方法】以自然放牧条件下3月龄幼龄和3岁龄成年牦牛(♂)背最长肌作为试验材料,利用双抗体夹心法、ATP酶染色法和PCR技术进行测定。【结果】(1)成年牛背最长肌Ⅰ型、ⅡA型和ⅡB型肌纤维直径、横切面积均高于犊牛,但ⅡB型肌纤维直径差异不显著(P>0.05),而犊牛背最长肌Ⅰ型、ⅡA型和ⅡB型肌纤维密度则显著高于成年牛(P<0.05)。(2)犊牛MyHCⅠ和MyHCⅡa基因的mRNA表达量显著成年牛(P<0.05),而MyHCⅡb与MyHCⅡx基因mRNA表达量则呈现相反趋势(P<0.05)。(3)两组肌肉总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)和丙二醛(MDA)等指标均无显著差异(P>0.05)。【结论】3岁龄牦牛与3月龄牦牛相比,降低了氧化性肌纤维类型,影响其肉品质,同时抗氧化能力差异不显著。【Objective】To study the antioxidant capacity in yak muscle and histology characteristics of muscle fiber.【Method】With natural grazing conditions in March and three yaks(came)back muscle as test material,using double antibody clip art,atpase staining method and real-time fluorescence quantitative polymerase chain reaction(polymerase chain reaction,PCR)technology were determined.【Result】(1)The diameter and cross-sectional area of longissimus dorsi muscle typeⅠ,typeⅡA and typeⅡB of adult cows were higher than those of calves,but there was no significant difference in the diameter of muscle fiber of typeⅡB(P>0.05),while the muscle fiber density of typeⅠ,typeⅡA and typeⅡB of calves was significantly higher than that of adult calves(P<0.05).(2)The calf MyHCⅠand MyHCⅡa gene m RNA expression of adult cattle was significantly higher than those of calves(P<0.05),while MyHCⅡb and MyHCⅡx gene m RNA expression presented contrary trend(P<0.05).(3)The total antioxidant capacity(T AOC)and superoxide dismutase(SOD),glutathione peroxidase(GSH-PX)and catalase(CAT)and malondialdehyde(MDA),and other indicators of muscles showed no significant difference between two groups(P>0.05).【Conclusion】Above all,the oxidizing muscle fiber types and meat quality of yak were decreased with age,while the antioxidant capacity not obviously increased at the same time.

关 键 词：牦牛 组织学特性 肌球蛋白重链 ATP酶染色 抗氧化指标 

分 类 号：S823.85[农业科学—畜牧学]