乌珠穆沁羊骨骼肌肌纤维组织学特性及MyHC表达量变化分析

发布时间：2018-04-21 07:04

  本文选题：乌珠穆沁羊 + 骨骼肌　； 参考：《内蒙古农业大学》2017年硕士论文

【摘要】：本实验采用6月龄、9月龄、12月龄与18月龄乌珠穆沁羊为研究对象,屠宰后取半腱肌、背最长肌、肱三头肌和股二头肌。利用ATPa.se组织化学染色法进行肌纤维染色,探索不同月龄不同部位骨骼肌的肌纤维密度、类型的百分比、面积比例及直径等组织学特性的变化;测定不同月龄乌珠穆沁羊各部位骨骼肌中肌球蛋白重链相关基因的表达水平;检测各样品硬度、咀嚼度及恢复性等品质指标。结果显示:随着月龄的增加各种肌纤维的直径及横截面积随之增加,而单位面积肌纤维的数量会减少。从肌肉组织中不同类型肌纤维的百分比来看,Ⅱb型肌纤维百分比较多、其次为Ⅱa型肌纤维和Ⅰ型肌纤维。整体上随着月龄的增加Ⅱb型肌纤维含量缓慢的增多,尤其背最长肌中Ⅱb型肌纤维的变化较为明显。基因表达结果显示MyHC Ⅰ表达量在6月龄到9月龄有稍微的增长,在12月龄和18月龄都有所降低。MyHC Ⅱa表达量在9月龄时变化不显著,12月龄开始降低,18月龄时达到最低值。MyHCⅡb和MyHCⅡx的表达量随着月龄的增加显著增加。相同月龄不同部位之间相比背最长肌MyHCⅡb表达量明显大于其他三个部位。从质构仪检测到的数据能看出乌珠穆沁羊随着月龄的增加肉质变得较硬,咀嚼度提高。因此月龄越大肌肉的嫩度越差。在四个不同部位之间背最长肌的变化最为明显。相关性数据显示肉的硬度和咀嚼度与MyHC Ⅰ和MyHC Ⅱ呈负相关性、与MyHC Ⅱx和MyHCⅡb呈正相关性、还与肌纤维密度呈负相关性,与肌纤维直径呈正相关性。
[Abstract]:In this experiment, Uzhimuqin sheep (6 months old, 9 months old, 12 months old and 18 months old) were used as research objects. After slaughtering, the semitendinosus muscle, the longest dorsal muscle, triceps brachii muscle and biceps femoris muscle were taken. ATPa.se histochemical staining was used to study the changes of muscle fiber density, percentage of type, area ratio and diameter of skeletal muscle at different months of age. The expression levels of myosin heavy chain related genes in skeletal muscle of different month old Wudhumqin sheep were determined and the quality indexes such as hardness chewing degree and recovery of each sample were detected. The results showed that the diameter and cross-sectional area of muscle fibers increased with the increase of age, but the number of muscle fibers per unit area decreased. According to the percentage of different types of muscle fiber in muscle tissue, the percentage of type 鈪，

本文编号：1781402