| 摘要: |
| 【目的】 比较滩羊、蒙古羊和小尾寒羊BMPR-IB基因的多态性，分析不同基因型对产羔数的影响，为绵羊繁殖力的标记辅助选择和育种提供理论依据。【方法】 利用PCR-RFLP方法检测和分析BMPR-IB基因的多态性，通过最小二乘分析方法研究不同基因型对产羔数的影响。【结果】 （1）滩羊和小尾寒羊均发现了++、B+和BB 3种基因型，其基因型频率分别为0.660，0.240，0.100和0.118，0.353，0.529，+和B的基因频率分别为0.780，0.220和0.294，0.706，蒙古羊仅表现++ 1种基因型；滩羊、小尾寒羊BMPR IB基因位点的多态信息含量(PIC)分别为0.439和0.501，表现为中度多态(0.25<PIC<0.5)和高度多态(PIC>0.5)；（2）小尾寒羊BB基因型个体平均产羔数较B+基因型多0.541只，差异达显著水平(P<0.05)，较++基因型多1.208只，差异达极显著水平(P<0.01)；滩羊BB基因型个体平均产羔数较B+和++基因型分别多0.076和0.159只，差异均不显著(P>0.05)。【结论】 （1）小尾寒羊和滩羊BMPR-IB基因编码序列第746位相邻2个碱基处发生了与布鲁拉美利奴绵羊(Booroola Merino)相同的突变(A746G)；（2）BMPR-IB基因位点的突变基因B可能是控制小尾寒羊和滩羊多胎性能的主效基因，或者是与之紧密连锁的遗传标记，可以用于提高繁殖力的标记辅助选择和育种工作。 |
| 关键词: 滩羊 蒙古羊 小尾寒羊 BMPR-IB基因 产羔数 |
| DOI： |
| 分类号: |
| 基金项目:宁夏滩羊选育及养殖配套技术与示范推广项目 |
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| Genetic polymorphism of BMPR-IB gene and effect on litter size in three sheep breeds |
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TIAN Xiu e，SUN Hong xia， WANG Yong jun,TIAN Xiu e，SUN Hong xia， WANG Yong jun,TIAN Xiu e，SUN Hong xia， WANG Yong jun
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| Abstract: |
| 【Objective】 The study compared the gene polymorphism of BMPR-IB gene in the Tan sheep,Mongolian Sheep and Small Tailed Han Sheep,and analyzed the effect on the litter size of the different genotype,which would provide a theoretical basis for marker assisted selection and breeding for prolificacy in sheep.【Method】 The gene polymorphism of BMPR-IBgene was analyzed by PCR-RFLP and the effect on litter size of different genotypes was studied by least squares mean.【Result】 (1)There were three genotypes ++,B+ and BB in the Tan Sheep and Small Tailed Han Sheep,the genotype frequencies were 0.660，0.240，0.100 and 0.118,0.353,0.529 respectively,0.780，0.220 and 0.294，0.706 were gene frequencies of + and B,and only ++ genotype existed in Mongolian Sheep.The polymorphism information contents (PIC) were 0.439 and 0.501 in the Tan Sheep and Small Tailed Han Sheep,which means moderate diversity (0.25<PIC<0.5)and high diversity (PIC>0.5) respectively.(2)The average litter size of Small Tailed Han Sheep with genotype BB had 0.541 (P<0.05) and 1.208 (P<0.01) lambs more than B+ and ++ genotypes.Tan Sheep were more than 0.076 and 0.159 (P>0.05) lambs.【Conclusion】 (1) There is the same mutation in BMPR-IB gene’s consecutive two basic (A746G) of Small Tailed Han Sheep and Tan Sheep as that of the Booroola Merino;(2) The B gene of BMPR-IBgene mutation locus may be a major gene which affects the prolificacy trait of Tan Sheep and Small Tailed Han Sheep or it is regarded as a genetic makers closely linked to target gene and could be as a marker assisting selection and breeding of improve fecundity. |
| Key words: Tan Sheep Mongolian Sheep Small Tailed Han Sheep BMPR-IBgene litter size |
