猪3号染色体上与产仔性状和窝内仔猪初生重整齐度显著关联的标记鉴定

试验旨在寻找与猪产仔性状和窝内仔猪初生重整齐度显著关联的分子标记，为猪繁殖性状的遗传改良提供依据。在课题组前期进行的猪全基因组清扫分析的基础上，选定猪3号染色体上的2个SNPs位点（rs338309012和rs335824784），利用目标序列捕获测序分型技术，在丹系大白猪和美系大白猪群中对这2个SNPs位点与猪产仔性状（包括总产仔数、产活仔数、死胎及木乃伊胎数等）及窝内仔猪初生重整齐度进行关联分析。结果显示，rs338309012位点与总产仔数、木乃伊胎数显著关联（P<0.05），AC基因型母猪的总产仔数、木乃伊胎数均显著高于CC基因型（P<0.05）；rs335824784位点与有效活仔数、木乃伊胎数显著关联（P<0.05），与产活仔数和死胎数极显著关联（P<0.01），不同基因型对产活仔数和有效活仔数的影响为GG > CG > CC，与之相反，对窝内仔猪初生重的变异系数、死胎及木乃伊胎数的影响为GG < CG < CC。因此，rs335824784位点GG基因型猪不仅产活仔数多，而且窝内仔猪初生重整齐，死胎和木乃伊胎数低，可以作为提高猪产仔性状和窝内仔猪初生重整齐度的分子标记。

Identification of Markers Significantly Associated with Litter Size Traits and Uniformity of the Piglet's Birth Weight on Porcine Chromosome 3

This study was aimed to find the molecular markers significantly associated with litter size traits and uniformity of the piglet's birth weight,and provided a basis for genetic improvement of reproductive traits in pigs.This study was based on the genome-wide selective sweep analysis of pig conducted by the research group in the previous studies,two SNPs (rs338309012 and rs335824784) on porcine chromosome 3 were selected,and the genotyping-in-thousand by sequencing was used,the relationship between two SNPs and litter size traits (including total number born,total number born alive,number of stillborn pigs and number of mummified pigs,etc.) and the uniformity of the piglet's birth weight was association analyzed in Danish Yorkshire and American Yorkshire pigs.The results showed that rs338309012 were significantly associated with the total number born and the number of mummified pigs (P<0.05),and the total number born and the number of mummified pigs of AC genotype sows was significantly higher than CC genotype (P<0.05).rs335824784 was significantly associated with the effective number of born alive and the number of mummified pigs (P<0.05),and was also extremely significantly associated with the total number born alive and the number of stillborn pigs (P<0.01).The effect of different genotypes on the total number born alive and effective number of born alive were GG > CG > CC.On the contrary,the effect of different genotypes on the coefficient of variation of the birth weight of piglets,the number of dead and mummified fetuses were GG < CG < CC.Thus,the GG genotype sows with rs335824784 not only had more total number born alive,but also had regular piglet's birth weight and lower number of stillborn and mummified pigs,which could be used as a molecular marker to improve the litter size traits and uniformity of the piglet's birth weight.