1 Hospital Veterinário da UTAD, Escola Ciências Agrárias e Veterinárias (ECAV) - Universidade de Trás-os-Montes e Alto Douro, PO Box 1013, 5000-801 Vila Real, Portugal.
2 Centro de Estudos Ciências Agrárias e Veterinárias (CECAV) - Universidade de Trás-os-Montes e Alto Douro, PO Box 1013, 5000-801 Vila Real, Portugal.
Animal. 2014 Mar;8(3):354-9. doi: 10.1017/S1751731113002218. Epub 2013 Dec 13.
Most donkey and local horse breeds are vulnerable to extinction as mechanization of agriculture progress throughout the world. The present study analyzed the pedigree and herd records of the donkey Asinina de Miranda breed (RAM), identifying genealogical and human factors that may affect the breed genetic diversity in the future and suggesting suitable strategies to breed preservation, early on the conservation program. The breeding rate was very low, with a ratio of foaling/live animals of 0.23 (178/760). The estimated number of founders and ancestors contributing to the reference population was 128 and 121. The number of founder herds in the reference population was 64, with an effective number of founder herds for the reference population of 7.6. The mean age of herd owners was 65.50 ± 0.884 years, with a negative association among the herd size and owner's age (P<0.001). In contrast, the size of the herd and the ownership of a male were both positively associated (P<0.001) with the herd number of in-born foals. Both the owners' age and the herd location (RAM home region v. dispersal region) were negatively associated with the foaling number (P<0.001). The main identified risk factors were: low breeding rates; low number of males and their unequal contribution to the genetic pool; unequal contribution of the herds to genetic pool; and advanced age of herd owners.
随着世界各地农业机械化的发展，大多数驴和本地马品种都面临灭绝的危险。本研究分析了 Miranda 驴品种（RAM）的系谱和畜群记录，确定了可能影响未来品种遗传多样性的遗传和人为因素，并提出了在保护计划早期适合繁殖保存的策略。繁殖率非常低，产仔/活畜比例为 0.23（178/760）。对参考群体有贡献的创始人数量和祖先数量估计分别为 128 和 121。参考群体中的创始畜群数量为 64 个，参考群体的有效创始畜群数量为 7.6。畜群所有者的平均年龄为 65.50±0.884 岁，畜群规模与所有者年龄之间呈负相关（P<0.001）。相比之下，畜群规模和拥有雄性与新生驹的畜群数量呈正相关（P<0.001）。畜群所有者的年龄和畜群所在地（RAM 原籍地区与分散地区）与产仔数量呈负相关（P<0.001）。主要确定的风险因素包括：繁殖率低；雄性数量少，对遗传库的贡献不均等；畜群对遗传库的贡献不均等；以及畜群所有者年龄较大。
