不同类型阿勒泰羊毛色关键基因筛选及选育方向分析

发布时间：2018-02-13 13:44

本文关键词： 阿勒泰羊毛色 ASIP基因 MC1R基因选育方向　出处：《石河子大学》2015年硕士论文　论文类型：学位论文

【摘要】：阿勒泰羊是新疆优良的地方绵羊品种,经过上千年的自然驯化和人工选育,阿勒泰羊现已形成在放牧条件下生长发育快、肉脂生产性能高等特点。本研究以不同毛色的阿勒泰羊为试验对象,揭示阿勒泰羊毛色的关键基因以及毛色与部分遗传性状的关系,根据不同毛色绵羊的遗传特点,制定相应的选育方向,为培育特色阿勒泰羊毛色品种打下坚实的基础。试验通过组建单一毛色(棕色、黑色、白色)的阿勒泰羊群体,测定其部分遗传指标,利用单链构象多态性(PCR-SSCP)技术对与绵羊毛色性状相关的候选基因(ASIP、MC1R)进行多态性研究和相关性分析,初步得到控制阿勒泰羊毛色的关键基因及毛色与生长发育、繁殖性状、肉用性状、毛用性状的关系。同时结合调研结果,提出符合富蕴县推广应用的阿勒泰羊选育方案(草案)。结果表明:(1)白色阿勒泰羊0-6月龄生长速度最快,总增重、日增重水平与棕色和黑色阿勒泰羊相比差异显著(P0.05);6月龄时,棕色阿勒泰羊体尺各测定指标总体高于其它两种毛色的阿勒泰羊。3种毛色的阿勒泰羊毛长与剪毛量间差异显著(P0.05),其中白色阿勒泰羊毛长和剪毛量最大,白色阿勒泰成年母羊的产羔数显著高于棕色和黑色阿勒泰母羊的产羔数(P0.05),但羔羊的存活率较低,造成这一现象的原因可能是由于白色阿勒泰成年母羊产羔数较多,母羊自身奶水不足,无法满足羔羊健康生长所需营养,导致羔羊自身免疫力低下所致。不同毛色阿勒泰羊泌乳性能差异不显著(P0.05),说明产奶量与毛色不相关。(2)ASIP-2和ASIP-4引物扩增片段均存在多态性,ASIP-3引物扩增片段不存在多态性。PCR-SSCP的结果显示ASIP基因的外显子2中存在3种基因型,分别为野生型N5N9、缺失型N5D5和N5D9,这3种基因型在不同毛色的阿勒泰羊群体中分布差异不显著(P0.05)。MC1R-4位点分别存在3种不同的基因型,即CC型、DD型、DE型,黑色被毛的阿勒泰羊群体主要以DE型为主,基因型频率为0.46;白色和棕色的阿勒泰羊群体主要以DD型为主,基因型频率分别为0.39和0.37。经分析比较,发现MC1R-4位点的这3种基因型在不同毛色的阿勒泰羊中的分布差异不显著(P0.05)。综上所述,结合毛色相关候选基因的多态性分析与阿勒泰羊生产性能指标测定结果,可以得出:白色阿勒泰羊适合用作肥羔生产和羊毛毡生产方向发展,而棕色阿勒泰羊和黑色阿勒泰羊更适合肉用。
[Abstract]:Altay sheep are excellent local sheep breeds in Xinjiang. After thousands of years of natural domestication and artificial breeding, Altay sheep have now grown rapidly under grazing conditions. In this study, the key genes of Altay wool color and the relationship between wool color and some hereditary traits were revealed, according to the genetic characteristics of sheep with different wool colors. In order to lay a solid foundation for the breeding of special Altay wool varieties, the experiment was conducted to determine some genetic indexes of Altay sheep with a single coat color (brown, black, white). A single strand conformation polymorphism (SSCP) PCR-SSCP technique was used to study and analyze the polymorphism of the candidate gene ASIPMC-1R, which is related to the color traits of wool. The key genes controlling the color of Altay wool, the color of wool, the growth and development of wool, and the reproductive traits were preliminarily obtained. The relationship between meat traits and wool traits. At the same time, according to the results of investigation, the breeding scheme of Altay sheep (draft) suitable for the popularization and application of Fuyun County was put forward. The results showed that the white Altay sheep grew fastest in 0-6 months of age and gained total weight. Compared with brown and black Altay sheep, ADG was significantly different at 6 months of age. The body size of brown Altay sheep was higher than that of the other two kinds of Altay sheep. The difference between the length and shearing of Altay wool was significant (P0.05), and the white Altay wool was the largest in length and shearing. The lambing size of white Altay adult ewe was significantly higher than that of brown and black Altay ewe, but the survival rate of lambs was lower. The reason for this phenomenon may be that white Altay adult ewe have more lambs. The ewe's own milk is not enough to meet the needs of the lamb's healthy growth. There was no significant difference in lactation performance between different wool color Altay sheep (P 0.05), which indicated that milk yield was not correlated with wool color. ASIP-2 and ASIP-4 primer amplified fragments were both polymorphic and not polymorphic. The results of PCR-SSCP showed that there were three genotypes in exon 2 of ASIP gene. Wild type N5N9, deletion type N5D5 and N5D9 were found respectively. There were no significant differences in the distribution of these three genotypes in different coat color populations of Altay sheep. There were three different genotypes at the locus of P0.05U. MC1R-4, namely, CC type and DD type. The main genotype frequency of the black wool Altay sheep was DE, and the frequency of genotype was 0.46, while that of white and brown Altay sheep was mainly DD, the genotype frequencies were 0.39 and 0.37, respectively. It was found that there was no significant difference in the distribution of the three genotypes of the MC1R-4 locus among the Altay sheep with different wool colors. In conclusion, the results of the analysis of the polymorphism of the candidate genes associated with wool color and the determination of the production performance index of Altay sheep were summarized. It can be concluded that white Altay sheep is suitable for fattening production and wool felt production direction, while brown Altay sheep and black Altay sheep are more suitable for meat use.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S826

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