Genetic diversity and population structure were analyzed using the historical and current pedigree information of the Arabian (PRá), Spanish Purebred (PRE), and Hispano-Arabian (Há) horse breeds. Genetic diversity parameters were computed and a canonical discriminant analysis was used to determine the contributions of ancestor breeds to the genetic diversity of the Há horse. Pedigree records were available for 207,100 animals born between 1884 and 2019. Nei’s distances and the equivalent subpopulations number indicated the existence of a highly structured, integrated population for the Há breed, which is more closely genetically related to PRá than PRE horses. An increase in the length of the generation interval might be an effective solution to reduce the increase in inbreeding found in the studied breeds (8.44%, 8.50%, and 2.89%, for PRá, PRE, and Há, respectively). Wright’s fixation statistics indicated slight interherd inbreeding. Pedigree completeness suggested genetic parameters were highly reliable. High GCI levels found for number of founders and non-founders and their relationship to the evolution of inbreeding permit controlling potential deleterious negative effects from excessively frequent mating between interrelated individuals. For instance, the use of individuals presenting high GCI may balance founders’ gene contributions and consequently preserve genetic diversity levels (current genetic diversity loss in PRá, PRE, and Há is 6%, 7%, and 4%, respectively).

中文翻译：

---

西班牙和阿拉伯纯种马对西班牙裔-阿拉伯马遗传多样性和种群结构贡献的判别典范分析

使用阿拉伯（PRá），西班牙纯种（PRE）和西班牙裔-阿拉伯（Há）马品种的历史和当前谱系信息分析了遗传多样性和种群结构。计算了遗传多样性参数，并使用经典判别分析来确定祖先品种对Há马的遗传多样性的贡献。有家谱记录可记录1884年至2019年之间出生的207,100只动物。Nei的距离和同等的亚种群数量表明，Há品种存在高度结构化的整合种群，与PRá相比，与PRá的亲缘关系更为密切。增加世代间隔的长度可能是减少研究品种中近交繁殖增加的有效解决方案（PRá，PRE，和Há）。赖特的注视统计数据表明有少量近亲繁殖。家谱完整性表明遗传参数高度可靠。对于创始人和非创始人的数量，发现其高GCI水平及其与近亲进化的关系，可以控制因相互关联的个体之间过度频繁地交配而造成的潜在有害负面影响。例如，使用表现出高GCI的个体可以平衡创始人的基因贡献，从而保持遗传多样性水平（PRá，PRE和Há目前的遗传多样性损失分别为6％，7％和4％）。对于创始人和非创始人的数量，发现高的GCI水平及其与近亲进化的关系，可以控制因相互关联的个体之间过度频繁地交配而可能产生的有害负面影响。例如，使用表现出高GCI的个体可以平衡创始人的基因贡献，从而保持遗传多样性水平（PRá，PRE和Há目前的遗传多样性损失分别为6％，7％和4％）。对于创始人和非创始人的数量，发现高的GCI水平及其与近亲进化的关系，可以控制因相互关联的个体之间过度频繁地交配而可能产生的有害负面影响。例如，使用表现出高GCI的个体可以平衡创始人的基因贡献，从而保持遗传多样性水平（PRá，PRE和Há目前的遗传多样性损失分别为6％，7％和4％）。