【作者】 王鑫；

【导师】 陈祥；

【作者基本信息】 贵州大学 ， 动物遗传育种与繁殖， 2018， 硕士

【摘要】 黔北麻羊属短毛皮肉兼用品种,具有适应性强、耐粗饲、产肉性能好、膻味轻、肉质好、板皮品质优良等特点,是杂交利用和培育新品种的良种素材。本研究以黔北麻羊为试验对象,开展黔北麻羊与波尔山羊、南江黄羊、努比亚羊杂交前后肉质特性研究,以影响肉质性状的Myf5、Myf6基因为候选基因,采用DNA混池法和直接测序等技术分析黔北麻羊中Myf5、Myf6基因的多态性,采用qPCR等技术检测Myf5、Myf6基因在黔北麻羊不同组织部位中的表达量,进一步对Myf5、Myf6基因的SNPs位点及表达量与黔北麻羊肉质性状指标进行关联性分析,旨在探究Myf5、Myf6基因的表达量对黔麻北羊肉质性状的影响,为黔北麻羊的选育及开发利用提供理论依据。研究结果如下:1、黔北麻羊肉质特性研究黔北麻羊与波尔山羊杂交后代(波黔F1)在宰前活重、胴体重和眼肌面积等屠宰性能指标与粗蛋白和粗脂肪等肉质指标较黔北麻羊均有一定程度的改善;黔北麻羊与南江黄羊杂交后代(南黔F1)在胴体重、净肉重和眼肌面积等屠宰性能指标与失水率和粗蛋白等肉质指标较黔北麻羊均有一定程度的改善,努比亚羊与黔北麻羊(努黔F1)在宰前活重和眼肌面积等指标较黔北麻羊均有一定程度的改善。波黔F1(81.04±2.250)、南黔F1(77.679±2.31)和努黔F1(81.04±2.250)在氨基酸指标上各种氨基酸含量比例均衡,但均略低于较纯种黔北麻羊(82.7735±3.4845);不饱和脂肪酸含量和饱和脂肪酸含量均略高于纯种黔北麻羊;在不同肌肉组织中(背最长肌、臂三头肌和股二头肌)波黔F1、南黔F1和努黔F1较黔北麻羊的肌纤维直径略粗,肌纤维密度十分相近;杂交组合中波黔F1杂交改良效果最佳。2、Myf5和Myf6基因的多态性检测及与其肉质指标的关联分析黔北麻羊和贵州黑山羊在Myf5基因第1外显子A270C处发现1个SNP位点,在Myf6基因中没有检测出多态位点,不具有多态性。进一步对Myf5基因多态位点不同基因型与肉质性状指标进行关联分析,发现不同基因型对黔北麻羊肉质指标存在显著差异(P<0.05)。3、Myf5和Myf6基因在黔北麻羊相关组织表达量的研究对于Myf5基因,在黔北麻羊的心、肝、脾、肺、肾、背最长肌、股二头肌和臂三头肌8个组织中均检测到其mRNA表达,且呈组织差异性表达,由高到低依次为臂三头肌、股二头肌、背最长肌、肾脏、肝脏、心脏、脾脏、肺脏;在3个肌肉组织中黔北麻羊Myf5基因mRNA的表达量极显著高于其他部位组织(P﹤0.01)。对于Myf6基因,在黔北麻羊的8个组织中均检测到Myf6基因mRNA的表达,其中在臂三头肌组织中表达量最高,脾脏中最低;在3个肌肉组织中的Myf6基因mRNA表达量极显著高于其他部位组织(P﹤0.01)。更多还原

【Abstract】 Qianbei Brown Goat was a kind of mutton with short hair and skin with an excellent local goat breed in Guizhou.It has the characteristics such as strong adaptability,rough feeding,good meat performance,light odor,good meat quality and good quality of the skin.It is a good material for hybrid utilization and cultivation of new varieties.The Qianbei Brown goat was treated as test subject,Study on the meat quality before and after hybridization between Qianbei Brown Goat and Boer Goat,Nanjiang Yellow Goat and Nubian Goat.Myf5 and Myf6 were candidate genes in this study as influencing meat quality traits.The polymorphism of Myf5 and Myf6 gene in Qianbei Brown Goat was analyzed by DNA mixed pool method and directly sequencing.The expression of Myf5 and Myf6 gene in different tissues of Qianbei Brown Goat were detected by qPCR techniques.Furthermore,the correlation analysis was carried out on the meat quality of Qianbei Brown Goat.Objective to explore the effect of Myf5 and Myf6 gene expression on the characteristics of mutton in Qianbei Brown Goat.In order to provide theoretical basis for breeding of good meat quality Qianbei Brown Goat and also provide theoretical basis for development and utilization.The main results of this study are as follows:1.The meat performance measurement of Qianbei Brown GoatQianbei Brown Goat and Boer Goat hybrid later generation(Boer and QianF1)in the slaughtering performance indexes such as live weight,carcass weightand eye muscle area,etc..and in the meat quality indexes crude protein and crude fat,etc..were compared,Qianbei Brown Goat was improved to some extent.and Qianbei Brown Goat and NanjiangYellow Goat(Nan and QianF1)in the slaughtering performance indexes such as carcass weight,pure meat weightand eye muscle area,etc..and in the meat quality indexes crude protein and water loss rate,etc..were compared,Qianbei Brown Goat was improved to some extent.Qianbei Brown Goat and Nubian Goat(Nubian and QianF1)in the slaughtering performance indexes such as live weight and eye muscle area,and so on.were compared,Qianbei Brown Goat was improved to some extent.The proportion of amino acid content in Boer and QianF1(81.04±2.250),Nan and Qian F1(77.679±2.31)and Nubian and QianF1(81.04±2.250)were balanced in amino acid index,but it was slightly lower than that of purebred Qianbei Brown Goat(82.7735±3.4845).The contents of unsaturated fatty acids and saturated fatty acids were slightly higher than those of pure Qianbei Brown Goat.In different tissues(longissimus dorsal muscle,triceps arm muscle and biceps flexor muscle),the muscle fiber diameter of Nan and QianF1 and Nubian and QianF1 were slightly thicker than that of Qianbei Brown Goat,and the density of muscle fiber was very close.The best effect of hybrid improvement in Boer and QianF1 in the hybridization.2.Detection of Polymorphism of Myf5 and Myf6 Gene and its Association with Meat quality Index.A SNP locus was found at the exon-1 A270 C of Myf5 gene in Black Goat and Qianbei Brown Goat from Guizhou,but no polymorphic loci was detected in Myf6 gene.The correlation analysis between different genotypes of Myf5 gene polymorphism loci with meat quality traits was carried out.It was found that there was a significant difference between different genotypes in the meat quality indexes of Qianbei Brown Goat.3.The expression of Myf5 and Myf6 gene in the related tissue had been researched.The expression of Myf5 gene was detected in heart,liver,spleen,lung,kidney,longissimus dorsal muscle,biceps flexor muscle and triceps arm muscle of Qianbei Brown Goat.The expressions of Myf5 were detected in those tissues,and the expressions in different tissues were different.The order from high to low of expressions were triceps arm muscle,biceps flexor muscle,longest dorsal muscle,kidney,liver,heart,spleen and lung.The expression of Myf5 mRNA in three muscle tissues was significantly higher than that of other tissues(P < 0.01).For Myf6 gene,mRNA expression of Myf6 gene was detected in eight tissues of Qianbei Brown Goat,the order from high to low of expressions were triceps arm muscle,biceps flexor muscle,longest dorsal muscle,liver,heart,kidney,lung and spleen.The expression level in three muscle tissues was significantly higher than that in other tissues(P < 0.01).更多还原