不同饲养方式对苏尼特羊miRNAs表达及肉品质的影响研究

发布时间：2018-08-15 12:53

【摘要】：通过实时荧光定量PCR技术,以12月龄放牧和圈养苏尼特羊为研究对象,对两种饲养方式下苏尼特羊背最长肌、臂三头肌和股二头肌中8个miRNAs(miR-1、miR-206、miR-128、miR-486、miR-133、miR-23a、miR-30a、miR-223)和 prdm1、sox6、tnnc1、tnnt3、prox1mRNA的相对表达量进行测定,同时测定肉质指标和屠宰性能。分析miRNAs表达与mRNA表达、屠宰性能和肉品质的相关性,研究通过快肌基因(sox6、tnnt3)和慢肌基因(tnnc1、prox1)验证miRNA如何在mRNA水平上影响肉品质(色泽)。结果显示:放牧和圈养条件下8个miRNAs在苏尼特羊中均有表达,且放牧组整体上高于圈养组。8个miRNAs两两间都呈显著正相关,说明各miRNAs间可形成调控网络,协同发挥作用。在饲养方式对肉品质的影响中发现,放牧组生长性状(体长、体高、胸围)、宰前活重和胴体重显著高于圈养组(p0.05),圈养组屠宰率显著高于放牧组(p0.05);圈养组的臂三头肌中剪切力显著高于放牧组(p0.05),背最长肌中红度值显著高于放牧组(p0.05),放牧组的臂三头肌中红度值显著高于圈养组(p0.05)。两种饲养方式下,miR-1与净肉重总是呈显著正相关。miR-486与宰前活重显著正相关。推测miR-1和miR-486 一定程度的高表达可提高苏尼特羊产肉量。miR-30a与体高和净肉重在背最长肌中显著负相关。miR-133和miR-30a与红度值(a*)在背最长肌中极显著负相关,与亮度值(L*)在臂三头肌中显著正相关。miR-206与pH值在背最长肌和股二头肌中显著负相关。两种饲养方式下miRNA对肉品质(色泽)调控机理的初步验证中发现,miR-30a使快肌和慢肌基因mRNA表达量均下降,但是影响程度不显著,推测miR-30a对色泽的影响可能还存在其他调控机制。
[Abstract]:Using real-time fluorescence quantitative PCR technique, the relative expression levels of 8 miRNAs (miR-1tnc1tnc1tnnt3ntnt3prox1) and prdm1tnc1tnc1tnnt3prox1 mRNA in the longissimus dorsi muscle, triceps arm muscle and biceps femoris muscle of Sunita sheep under 12 months grazing and in captivity were determined by using real-time quantitative PCR technique, and the relative expressions of 8 miRNAs mRNA (miR-486 miR-486miR-133miR-23amiR-30amiR-30amiR-223) and prdm1soxtnc1tnnc1tnnt3 prox1 mRNA were determined. Meat quality index and slaughter performance were also measured. To analyze the correlation between miRNAs expression and mRNA expression, slaughter performance and meat quality, we studied how miRNA affects meat quality (color) at mRNA level by using fast muscle gene (sox6 tnnt3) and slow muscle gene (tnc1prox1). The results showed that 8 miRNAs were expressed in Sunita sheep under the condition of grazing and captivity, and the overall level of miRNAs in grazing group was higher than that in captivity group, and there was a significant positive correlation among 8 miRNAs groups, indicating that the regulatory network could be formed and synergistic effect could be exerted among miRNAs. In the influence of feeding mode on meat quality, it was found that the growth traits (body length, body height) of grazing group, In chest circumference, the live weight and carcass weight before slaughter were significantly higher than those in captivity group (p0.05), the slaughter rate in captivity group was significantly higher than that in grazing group (p0.05), the shear force in triceps arm muscle in captivity group was significantly higher than that in grazing group (p0.05), the redness of longissimus dorsi muscle was significantly higher than that in grazing group (p0.05), and that in captivity group was significantly higher than that in grazing group (p0.05). The value of redness of triceps arm muscle in grazing group was significantly higher than that in captivity group (p 0.05). There was a significant positive correlation between miR-1 and net meat weight under two feeding methods. MiR-486 was positively correlated with live weight before slaughter. It was inferred that the high expression of miR-1 and miR-486 could increase the meat yield of Sunita sheep. MiR-30a was negatively correlated with body height and net meat weight in the longissimus dorsi muscle. MiR-133 and miR-30a were significantly negatively correlated with the red value (a *) in the longissimus dorsi muscle. There was a significant negative correlation between L* and L* in triceps arm muscle. MiR-206 was negatively correlated with pH value in longissimus dorsi muscle and biceps femoris muscle. In the preliminary verification of the mechanism of miRNA regulating meat quality (color and color) under two feeding modes, it was found that miR-30a decreased the mRNA expression of both fast and slow muscle genes, but the effect was not significant. It was speculated that there might be other regulatory mechanisms in the influence of miR-30a on color and color.
【学位授予单位】：内蒙古农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S826;TS251.53

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