INRA, Animal Genetics and Integrative Biology, UMR 1313, Domaine de Vilvert, F-78352 Jouy-en-Josas, France.
J Anim Sci. 2011 Jun;89(6):1719-30. doi: 10.2527/jas.2010-3469.
Pedigree collected by the Interbeef service allowed genetic diversity to be assessed by using pedigree analyses for the European Charolais (CHA) and Limousin (LIM) cattle populations registered in national herdbooks in Denmark (DNK), France (FRA), Ireland (IRL), Sweden (SWE), and, solely for the LIM breed, the United Kingdom (UK). The CHA data set included 2,563,189 calves with weaning performance, of which 96.1% were recorded in FRA, 3.0% in SWE, 0.5% in IRL, and 0.4% in DNK. The LIM data set included 1,652,734 calves with weaning performance, of which 91.9% were recorded in FRA, 4.9% in UK, 1.8% in DNK, 0.9% SWE, and 0.5% in IRL. Pedigree files included 3,191,132 CHA and 2,409,659 LIM animals. Gene flows were rather limited between populations, except from FRA toward other countries. Pedigree completeness was good in all subpopulations for both breeds and allowed the pedigree to be traced back to the French population. A relatively high level of genetic diversity was assessed in each CHA and LIM subpopulation by estimating either effective population sizes (N(e) >244 and N(e) >345 in the CHA and LIM subpopulations, respectively), relationship coefficients within subpopulations (<1.3% in both breeds), or probability of gene origins. However, in each subpopulation, it was shown that founders and also ancestors had unbalanced genetic contributions, leading to a moderate but continuous reduction in genetic diversity. Analyses between populations suggested that all European CHA and LIM populations were differentiated very little. The Swedish CHA population was assessed as genetically more distant from the other CHA populations because of fewer gene flows from other countries and because of the use of North American sires to introgress the polled phenotype. In each European subpopulation, most of the main ancestors, which explained 50% of gene origin, were born in FRA. However, those main ancestors were different between countries. Moreover, in both breeds, the main ancestors, which explained 50% of the gene origin in DNK, IRL, SWE, and UK for the LIM breed, were found to be infrequently used in FRA. Those results were consistent with the low relationship coefficients estimated between subpopulations (<0.6% in both the CHA and LIM breeds). Therefore, in both breeds, each subpopulation may constitute a reservoir of genetic diversity for the other ones.
由 Interbeef 服务收集的系谱允许通过使用系谱分析来评估欧洲夏洛来牛（CHA）和利木赞牛（LIM）牛种群的遗传多样性，这些种群在丹麦（DNK）、法国（FRA）、爱尔兰（IRL）、瑞典（SWE）和英国（UK）的国家牛群登记册中进行了登记。CHA 数据集包括 2563189 头断奶表现的小牛，其中 96.1%在 FRA 记录，3.0%在 SWE 记录，0.5%在 IRL 记录，0.4%在 DNK 记录。LIM 数据集包括 1652734 头断奶表现的小牛，其中 91.9%在 FRA 记录，4.9%在 UK 记录，1.8%在 DNK 记录，0.9%在 SWE 记录，0.5%在 IRL 记录。系谱文件包括 3191132 头 CHA 和 2409659 头 LIM 动物。种群之间的基因流动相当有限，除了 FRA 向其他国家的流动。两个品种在所有亚种群中的系谱完整性都很好，并且允许追溯到法国种群。通过估计有效种群大小（CHA 亚种群中的 N(e)>244 和 N(e)>345，以及 LIM 亚种群中的 N(e)>345）、亚种群内的关系系数（<1.3%在两个品种中）或基因起源的概率，在每个 CHA 和 LIM 亚种群中都评估了相对较高的遗传多样性水平。然而，在每个亚种群中，都表明了创始人以及祖先具有不平衡的遗传贡献，导致遗传多样性的适度但持续减少。种群间的分析表明，所有欧洲的 CHA 和 LIM 种群都非常相似。瑞典的 CHA 种群被评估为与其他 CHA 种群的遗传距离较远，因为来自其他国家的基因流动较少，并且由于使用北美种公牛来引入无角表型。在每个欧洲亚种群中，解释基因起源 50%的主要祖先，大多数出生在 FRA。然而，这些主要祖先在不同的国家有所不同。此外，在两个品种中，解释 DNK、IRL、SWE 和 UK 中 LIM 品种基因起源 50%的主要祖先在 FRA 中使用频率较低。这些结果与亚种群之间估计的关系系数（CHA 和 LIM 品种均<0.6%）一致。因此，在两个品种中，每个亚种群都可能成为其他亚种群遗传多样性的储备库。
