食品科学 ›› 2021, Vol. 42 ›› Issue (7): 83-89.doi: 10.7506/spkx1002-6630-20200321-312

• 基础研究 • 上一篇    下一篇

饲养方式对苏尼特羊肌纤维组成和肉品质的影响及其调控机理

侯艳茹,苏琳,侯普馨,白艳苹,孙冰,赵丽华,黄凯飚,吕科,靳烨   

  1. (1.内蒙古农业大学食品科学与工程学院,内蒙古 呼和浩特 010018;2.乌拉特中旗农牧和科技局,内蒙古 乌拉特中旗 015300;3.内蒙古草原晶鑫食品有限责任公司,内蒙古 巴彦淖尔 015000)
  • 出版日期:2021-04-15 发布日期:2021-05-17
  • 基金资助:
    内蒙古自治区自然科学基金重大专项(2020ZD11);内蒙古自治区科技成果转化专项(2019CG066); 国家自然科学基金地区科学基金项目(31660439;32060519); “十三五”国家重点研发计划重点专项(2016YFE0106200);内蒙古自治区自然科学基金面上项目(2018MS03050)

Effect of Feeding Regimens on Muscle Fiber Type Composition and Meat Quality of Sunit Sheep and Underlying Regulatory Mechanism

HOU Yanru, SU Lin, HOU Puxin, BAI Yanping, SUN Bing, ZHAO Lihua, HUANG Kaibiao, LÜ Ke, JIN Ye   

  1. (1. College of Food Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China;2. Agriculture, Animal Husbandry and Science and Technology Bureau, Wulate Middle Banner 015300, China; 3. Inner Mongolia Caoyuanjingxin Food Co. Ltd., Bayannur 015000, China)
  • Online:2021-04-15 Published:2021-05-17

摘要: 本实验以不同饲养方式下(放牧和舍饲)苏尼特羊背最长肌为材料,分析其肉品质指标的差异性,并利用ATPase染色法和实时荧光定量聚合酶链式反应技术对肌纤维类型进行划分,同时对相关代谢酶活力以及肌纤维转化相关调控基因mRNA表达量进行分析。结果表明,放牧组的胴体质量、L*值、剪切力和pH24值显著低于舍饲组(P<0.05或P<0.01);IIB型肌纤维数量比例和面积比例,I型、IIA型和IIB型肌纤维直径和肌纤维横截面积,乳酸脱氢酶酶活力均显著低于舍饲组(P<0.05或P<0.01)。而放牧组IIA型肌纤维的数量比例和面积比例、MyHC I和MyHC IIX mRNA表达量、苹果酸脱氢酶和琥珀酸脱氢酶活力、AMPKα2和COX IV mRNA相对表达量显著高于舍饲组(P<0.05或P<0.01)。PGC-1α mRNA表达量在两种饲养方式下差异不显著(P>0.05)。综上所述,与舍饲相比,放牧饲养能提高肌纤维的AMPKα2 mRNA相对表达量,激活位于线粒体内膜上的细胞色素c氧化酶IV,提高肌肉的线粒体生物合成水平,增强肌肉的氧化代谢能力,使肌纤维类型由酵解型向氧化型转化,进而改善肉品品质。

关键词: 饲养方式;苏尼特羊;肌纤维组成;酶活力;肌纤维调控基因

Abstract: The effects of feeding regimens (pasture and confinement) on meat quality, muscle fiber type composition and key factors regulating muscle fiber type in the Longissimus dorsi muscle of Sunit sheep were investigated. The results showed that carcass mass (P < 0.05),L* value (P < 0.05), Warner-Bratzler shear force (WBSF) (P < 0.05), pH24 (P < 0.01), the number and area proportion of type IIB muscle fiber (P < 0.01), the diameter of type I, IIA and IIB (P < 0.01), the cross-sectional area of type I (P < 0.05), IIA (P < 0.01) and IIB (P < 0.01), and lactic dehydrogenase (LDH) activity (P < 0.01) in the pasture group were significantly lower than those in the confinement group. However, the number and area proportion of type IIA muscle fiber (P < 0.01), the mRNA expression of the MyHC I and MyHC IIX genes (P < 0.01), the activity of malate dehydrogenase (MDH) and succinate dehydrogenase (SDH) (P < 0.05), and the mRNA expression of the AMPKα2 and COX IV genes (P < 0.05 or 0.01) were significantly higher in the pasture group than those in the confinement group. The mRNA expression of the PGC-1α gene was no significantly different between the two groups (P > 0.05). Overall, the present study indicated that compared to confinement feeding, pasture feeding could augment the relative mRNA expression level of AMPKα2 in the muscle and activate cytochrome c oxidase IV (COX IV) in the mitochondrial inner membrane, thus promoting mitochondrial biogenesis, enhancing oxidative metabolism, inducing the transition of muscle fiber types from glycolyzed to oxidized types, and finally improving meat quality.

Key words: feeding regimens; Sunit sheep; muscle fiber type composition; enzymatic activity; muscle fiber type-related genes

中图分类号: