2个不同品种肉兔背最长肌肌纤维发育规律及相关基因表达比较分析

Comparative Analysis of Muscle Fiber Development and Related Gene Expression in Longissimus Dorsi Muscle of Two Different Breeds of Meat Rabbits

为研究四川白兔和新西兰兔背最长肌肌纤维发育规律以及肌纤维发育相关基因的表达情况,采集四川白兔和新西兰兔35、56、84日龄3个阶段背最长肌组织,利用石蜡切片技术研究背最长肌肌纤维发育规律,同时,应用实时荧光定量PCR检测MyoG、Myf5和MSTN等基因的表达量。结果显示:2个品种肉兔的肌纤维面积和直径均随着日龄的增加而增加,密度随着日龄的增加而减少,且密度减少趋势放缓。两品种间比较,四川白兔35、84日龄的肌纤维面积和直径显著低于新西兰兔,56日龄的面积和直径显著高于新西兰兔,四川白兔35、84日龄的密度显著高于新西兰兔,56日龄的密度显著低于新西兰兔。不同日龄基因表达比较,两品种均呈现MyoG表达先下调后上调,Myf5表达下调。品种间相比,新西兰兔MyoG、Myf5表达量高,四川白兔MSTN表达量高。综上所述,其研究有助于理解四川白兔和新西兰兔背最长肌发育规律,为进一步研究四川白兔和新西兰兔的肌肉生长发育调控机制提供理论参考。

In order to study the developmental pattern of the longest dorsal muscle muscle fibers and the expression of genes related to muscle fiber development in Sichuan white rabbits and New Zealand rabbits,the present experiment was conducted.In this experiment,the longest dorsal muscle tissues of Sichuan white rabbits and New Zealand rabbits were collected at the age of 35,56 and 84 days,and paraffin sections were taken to study the developmental pattern of myofibers of the longest dorsal muscle,meanwhile,real-time fluorescence PCR was applied to detect the expression of Myo G,Myf5 and MSTN genes.The results showed that the myofiber area and diameter of the two breeds of meat rabbits increased with the increase of age,and the density decreased with the increase of age,and the trend of density decrease slowed down.Comparing between the two breeds,the area and diameter of Sichuan white rabbits were significantly lower than those of New Zealand rabbits at 35 and 84 days of age,and significantly higher than those of New Zealand rabbits at 56 days of age,and the density was significantly lower than that of New Zealand rabbits at 56 days of age.Comparing gene expression at different days of age,both breeds showed that Myo G expression was first down-regulated and then up-regulated,and Myf5 expression was downregulated.Compared between breeds,Myo G and Myf5 expression was high in New Zealand rabbits and MSTN expression was high in Sichuan white rabbits.In summary,this study helps to understand the developmental pattern of the longest dorsal muscle of Sichuan white rabbits and New Zealand rabbits,and provides theoretical references for further research on the regulatory mechanism of muscle growth and development in Sichuan white rabbits and New Zealand rabbits.