中文摘要：

本研究旨在对仔猪均匀度进行表型与遗传分析,探究其与各繁殖性状之间的相关,为其在育种中应用奠定基础。试验选取某核心场近6年产仔记录,利用DMU软件和动物模型估计了仔猪均匀度的加性方差、与配公猪效应方差和永久环境效应方差,计算各品种该性状遗传力;并评估了大白猪仔猪均匀度与主要繁殖性状（总产仔数、产活仔数、初生窝重、断奶仔猪数和21日龄窝重）之间的表型和遗传相关。结果表明：品种、胎次和母猪分娩年季对仔猪均匀度均有显著影响（P〈0.05）;大白猪、长白猪和杜洛克猪遗传力分别达到0.059、0.065和0.027,与配公猪效应变化范围为0.008～0.014,永久环境效应变化范围为0.000～0.017;此外,表型与遗传相关结果较为接近,仔猪均匀度与总产仔数、产活仔数和初生窝重呈中等正相关,与断奶仔猪数和21日龄窝重相关均接近于0。随着产仔数的增加,仔猪整齐度逐渐减小。因此,在增加产仔数的同时,应考虑对仔猪均匀度的选择。

英文摘要：

The objective of this study was to analysis the phenotypic and genetic parameter of litter uniformity and to investigate its correlation with reproduction traits. This study selected recent birth records of certain core pig breeding farm. Animal model and DMU software were used to estimate variances of animal genetic （a） , service sire （0and permanent environment （pe）, then calculated the genetic parameter of different breeds. Moreover, we estimated the phenotypic and genetic correlation between litter uniformity and major reproduction traits （total number born （TNB）, number born alive（NBA）, litter weight at birth（LBW）, number weaned（NW） and litter weight at 21d（L21WT））. As a result, breed, parity and annual seasons significantly influence the litter uniformity （P〈0.05）; The heritabilities were 0.059, 0.065and 0.027 for largewhite, landrance and duroc, the range of variances of service sire and permanent environment were 0.008-0.014 and 0.000-0.017, respectively. In addition, The phenotypic and genetic correlation were closed, the correlation between litter uniformity and TNB, NBA and LBW were medium and positive, but the correlation between NW and L21WT were closed to 0.So, along with the increase and selection of the number of birth, we should take consideration of the selection of litter uniformity.