Brazilian hair sheep constitute a genetic diversity hotspot. These animals are found in the harsh environments of the Brazilian Northwest (semi-arid) region. Genotypes (50K SNP chip) from seven Brazilian sheep breeds (five hair and two coarse wool types) and 87 worldwide breeds were used to test for population structure, admixture and genetic diversity. Moreover, phylogenetic trees evaluating migration events between genetic groups were built. Brazilian Somali, a fat-tailed breed, had a close relationship with East African breeds and clustered distinctly from other Brazilian breeds. Brazilian Blackbelly and Barbados Blackbelly had a close relationship. The Morada Nova breed did not show close relationships with European or African breeds, revealing a single migration event from an Algerian hair breed. Brazilian Fat-tail and Morada Nova share a common ancestor, but the former showed introgressions from Brazilian Somali and Afrikaner breeds, explaining the fat-tail phenotype. The Santa Inês breed received a substantial contribution from Brazilian Bergamasca and showed an admixed origin with recent introgressions from other breeds, mainly from Suffolk. Furthermore, Brazilian Somali and Brazilian Fat-tail are the most endangered sheep genetic resources in Brazil and should be the focus for ex situ conservation programs. In conclusion, Brazilian hair sheep show an African origin and are characterized by diverse genetic composition, reinforcing the need for conservation of these genetic resources, and at the same time, this highly diverse group has variability that can be used in breeding programs.

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巴西毛羊品种的起源和种群结构

巴西毛羊构成遗传多样性热点。这些动物生活在巴西西北部（半干旱）地区的恶劣环境中。来自七个巴西绵羊品种（五种毛发和两种粗毛类型）和 87 个全球品种的基因型（50K SNP 芯片）用于测试种群结构、混合物和遗传多样性。此外，还建立了评估基因组之间迁移事件的系统发育树。巴西索马里人是一种肥尾品种，与东非品种关系密切，与其他巴西品种明显聚集。巴西黑腹和巴巴多斯黑腹有着密切的关系。Morada Nova 品种没有表现出与欧洲或非洲品种的密切关系，揭示了来自阿尔及利亚毛发品种的单一迁移事件。巴西肥尾和莫拉达诺瓦有着共同的祖先，但前者表现出来自巴西索马里和南非白种人的基因渗入，解释了肥尾表型。Santa Inês 品种获得了巴西贝加马斯卡的大量贡献，并显示出混合起源与其他品种（主要来自萨福克）最近的基因渗入。此外，巴西索马里和巴西肥尾是巴西最濒危的绵羊遗传资源，应成为重点关注的绵羊遗传资源。异地保护计划。总之，巴西毛羊起源于非洲，具有多样化的遗传组成，加强了保护这些遗传资源的必要性，同时，这个高度多样化的群体具有可用于育种计划的变异性。