摘要
用衡阳和永州２个外贸猪场１９９６～１９９８年间杜洛克、长白和大约克猪的生长和屠宰个体记录及ＲＡＰＤ分析数据，估计了平均日增重（ＡＤＧ）、屠宰率（ＤＲＰ）、背膘厚（ＢＦＴ）、后腿比例（ＨＬＰ）４个经济性状以及ＲＡＰＤ标记平均带纹相似系数（ＡＢＳ）的杂交效果参数，结果表明：４个经济性状的个体遗传效应（ｇＩ）和母本遗传效应（ｇＭ）显著（Ｐ＜０．０５）．日增重的个体杂优和母本杂优效应达显著水准（Ｐ＜０．０５）。但是，屠宰率、背膘厚和后腿比例３个性状的个体杂优效应和母本杂优效应均不显著（Ｐ＞０．０５）。ＲＡＰＤ标记ＡＢＳ的母本遗传效应估值为正，而杂优效应（ｈＩ和ｈＭ）估值为负值．杂交效果参数与生长和肉用性状的相关性研究表明，ＲＡＰＤ标记ＡＮＳ与平均日增重、屠宰率、背膘厚和后腿比例４个性状总的、全参数非特异性相关系数低（０．２７３５～０．４４１４），且不显著（Ｐ＞０．０５）．但是，部分参数的特异性相关系数与总相关系数相比，均有不同程度的提高（一０．８２４０～０．８９１８），其中平均日增重与ＲＡＰＤ标记ＡＢＳ的３个特异性杂交效果参数的相关系数分别达到显著（Ｐ＜０．０５）和极显著（Ｐ＜０．０１）水平。由此推测，用全参数的总?
Parameters of crossbreeding effect have been estimated for average daily gain (ADG), dressing percentage (DRP), backfat thickness (BFT),percent of hind legs (HLP), and average band-Sharing of RAPD markers, by using individual records of growth and meatproduction and genotypes of RAPD analysis in crosses of Duroc, Landrace and large White pigs from 1996 through 1998. The results indicate that significant individual and maternal genetic effects exist for all the 4 traits of growth and meat-production(P< 0.05). Effects of individual heterosis and maternal heterosis have also been found to be significant for ADG (P< 0.05), but not significant for DRP, BFT, and HLP (P> 0.05). Maternal genetic effect is positive and the effects of individual heterosis and maternal heterosis are negative for RAPD-marker ABS. Correlation analysis reveals that the total correlation,which includes all parameters at a time, is low and not significant The partial correlation,however, is more reasonable than total correlation,which consider 1 parametr each time, or 2 in case of heterosis. All 3 partial correlations between ADG and RAPD-marker ABS are significantly greater or smaller than zero (P < 0.05), among which the correlation for individual genetic effect is very significant (P< 0.01). It is therefore concluded that the efficiency of predicting heterosis is low by simply applying total correlation. Alternatively, estimation of parameters of crossbreeding effect for both economic traits and DNA markers provides a way of efficiently predicting heterosis for it dramatically increases the correlation between markers and traits of economical importance. Increasing QTL coverage (percent of markers linked to QTL) will as well contribute to improved accuracy of predicting heterosis. It is also implied from the partial correlations that while genomic similarity of crosses increases, individual genetic effect would increase, but that of individual heterosis and maternal heterosis would decreases.
基金
湖南省"九五"攻关计划(01-961-07)
湖南省自然科学基金(97JJY2005)&&
