Malm S, Fikse W F, Danell B, Strandberg E
Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.
J Anim Breed Genet. 2008 Dec;125(6):403-12. doi: 10.1111/j.1439-0388.2008.00725.x.
The aim of this study was to estimate genetic parameters and genetic trends for hip (HD) and elbow dysplasia (ED) in Swedish Rottweiler (RW) and Bernese Mountain Dog (BMD). Analyses were based on screening results of hip status for 14 693 RW and 8221 BMD and elbow status for 11 891 RW and 7963 BMD, as well as pedigree data for 16 614 RW and 9835 BMD, recorded by the Swedish Kennel Club. Components of (co)variance and breeding values were obtained with a mixed linear animal model. The model included the fixed effects of sex, birth month, age at screening and a combined random effect of clinic and year of examination. The need to include genetic groups for phantom parents in the model was evaluated by comparison of two different models: with and without genetic groups. Estimated heritabilities for HD and ED were between 0.34 and 0.42. The genetic correlation between the traits was weak and positive for RW (r(g) = 0.23 +/- 0.05) and not different from zero for BMD (r(g) = 0.06 +/- 0.06). F-statistics of the genetic group effects were not significant, implying that genetic groups do not need to be included in the model. Genetic trends indicated a genetic improvement in both traits. However, a faster genetic progress is expected if selection is based on predicted breeding values rather than phenotype. Based on the results, a statistical model for routine prediction of breeding values for HD and ED in Swedish dogs was suggested.
本研究的目的是估计瑞典罗威纳犬（RW）和伯恩山犬（BMD）髋关节发育不良（HD）和肘关节发育不良（ED）的遗传参数及遗传趋势。分析基于瑞典养犬俱乐部记录的14693只RW和8221只BMD的髋关节状况筛查结果、11891只RW和7963只BMD的肘关节状况筛查结果，以及16614只RW和9835只BMD的系谱数据。采用混合线性动物模型获得（协）方差分量和育种值。该模型包括性别、出生月份、筛查时年龄的固定效应以及诊所和检查年份的联合随机效应。通过比较两种不同模型（含遗传组和不含遗传组）评估在模型中纳入虚拟亲本遗传组的必要性。HD和ED的估计遗传力在0.34至0.42之间。性状间的遗传相关性在RW中较弱且为正（r(g) = 0.23 +/- 0.05），在BMD中与零无差异（r(g) = 0.06 +/- 0.06）。遗传组效应的F统计量不显著，这意味着模型中无需纳入遗传组。遗传趋势表明这两个性状都有遗传改良。然而，如果基于预测育种值而非表型进行选择，预计遗传进展会更快。基于这些结果，提出了一个用于瑞典犬HD和ED育种值常规预测的统计模型。
