Eisen E J, Pomp D
Department of Animal Science, North Carolina State University, Raleigh 27695-7621.
Genome. 1990 Apr;33(2):294-301. doi: 10.1139/g90-045.
Replicate differences were studied in lines of mice selected at 12 weeks of age for high (HF1, HF2) or low (LF1, LF2) right epididymal fat pad weight as a percentage of body weight (%EFP); for high (HL1, HL2) or low (LL1, LL2) hind carcass weight as a percentage of body weight (%HC); and randomly (RC1, RC2). Correlated traits were subcutaneous fat pad weight as a percentage of body weight (%SFP), water weight in hind carcass as a percentage of hind carcass weight (%WAT), body weights at 3, 6, and 12 weeks of age, and 3- to 6-week weight gain. Individual and maternal effects contributed to significant genetic drift for selected and correlated traits. No evidence indicated that drift was greater in selection treatments than in controls. Significant heterosis in replicate crosses within selection treatments was found for %HC in HL, LL, and LF and for %EFP in HF. Heterosis was insignificant in crosses of control replicates. Divergence in parental lines and replicate crosses was similar, indicating that differences in heterosis between high and low lines were small relative to divergence. Asymmetry tended to be greater between replicate crosses and parental lines, because selected replicates have greater average heterosis than control replicates. Multivariate discriminant function and Mahalanobis distance analysis of selected traits showed that divergence between replicates within selection treatments was much less than among selection treatments.
对12周龄时按右附睾脂肪垫重量占体重百分比（%EFP）选高（HF1、HF2）或选低（LF1、LF2）的小鼠品系；按后躯胴体重量占体重百分比（%HC）选高（HL1、HL2）或选低（LL1、LL2）的小鼠品系；以及随机选择（RC1、RC2）的小鼠品系的重复差异进行了研究。相关性状包括皮下脂肪垫重量占体重百分比（%SFP）、后躯胴体水分重量占后躯胴体重量百分比（%WAT）、3周龄、6周龄和12周龄时的体重以及3至6周龄时的体重增加。个体效应和母体效应导致所选性状和相关性状出现显著的遗传漂变。没有证据表明选择处理中的遗传漂变比对照中的更大。在选择处理内的重复杂交中，HL、LL和LF中的%HC以及HF中的%EFP存在显著杂种优势。对照重复杂交中的杂种优势不显著。亲本品系和重复杂交中的差异相似，表明高低品系之间杂种优势的差异相对于差异来说较小。重复杂交和亲本品系之间的不对称性往往更大，因为所选重复比对照重复具有更大的平均杂种优势。对所选性状进行多变量判别函数和马氏距离分析表明，选择处理内重复之间的差异远小于选择处理之间的差异。
