Faculdade de Agronomia e Medicina Veterinária, Campus Darcy Ribeiro, Universidade de Brasília, Asa Norte, Brasília, DF, 70910-900, Brazil.
Departamento de Ciências Fisiológicas, Instituto de Biologia, Campus Darcy Ribeiro, Universidade de Brasília, Asa Norte, Brasília, DF, 70910-900, Brazil.
Trop Anim Health Prod. 2021 Oct 28;53(6):525. doi: 10.1007/s11250-021-02971-1.
Among the animal species first introduced in Brazil during the country's discovery, horses (Equus caballus) stand out because of their evolutionary history and relationship with humans. Among the Brazilian horse breeds, the Pantaneiro draws attention due to its adaptative traits. Blood samples of 116 Pantaneiro horses were divided into six populations based on their sampling location, aiming to identify the existence of genetic structure and quantify genetic diversity within and between them. Populations were compared to elucidate genetic variability and differentiation better and assess the impact of Pantanal's natural geographic barriers on gene flow between populations. Data from the GGP Equine BeadChip (Geneseek-Neogen, 65.157 SNPs) was used to assess basic diversity parameters, genetic distance (F), principal component analysis (PCA), and population structure (ADMIXTURE) for the sampled animals. Mantel test was also performed to investigate the correlation between the populations' genetic and geographic distances. Results showed high genetic variability in all populations, with elevated levels of admixture in their structure. High levels of admixture make it challenging to establish a racial pattern and, consequently, populations within the breed, being that only one of the populations differentiated itself from the others. No significant correlations between genetic and geographic distances were observed, indicating that environmental barriers did not hinder gene flow between populations, and neither farmers' selection practices might have change breed genetic composition significantly. Low genetic distance and similar heterozygosity values were observed among populations, suggesting strong genetic proximity and low differentiation. Thereby, the Pantaneiro breed does not exhibit genetic subpopulations and could be considered, for conservation purposes, a single big population in the Panatnal region. This study will support sampling strategies for National genebank.
在巴西发现时引入的动物物种中，马（Equus caballus）因其进化历史和与人类的关系而引人注目。在巴西马品种中，潘塔内罗因其适应性特征而引人注目。根据采样地点，将 116 匹潘塔内罗马的血液样本分为六个群体，旨在确定是否存在遗传结构，并量化它们之间的遗传多样性。对群体进行比较，以更好地阐明遗传变异性和分化，并评估潘塔纳尔天然地理屏障对群体间基因流动的影响。使用 GGP 马珠芯片（Geneseek-Neogen，65,157 个 SNP）的数据评估了基本多样性参数、遗传距离（F）、主成分分析（PCA）和采样动物的群体结构（ADMIXTURE）。还进行了 Mantel 检验，以调查群体遗传和地理距离之间的相关性。结果表明，所有群体的遗传变异性都很高，其结构中的混合程度较高。高水平的混合使得建立种族模式变得困难，因此，该品种内的群体只有一个与其他群体区分开来。遗传距离和地理距离之间没有观察到显著相关性，这表明环境障碍并没有阻碍群体间的基因流动，农民的选择实践也没有显著改变品种的遗传组成。群体之间观察到低遗传距离和相似的杂合度值，表明遗传关系密切且分化程度低。因此，潘塔内罗品种没有表现出遗传亚群，可以考虑为保护目的，将潘塔纳尔地区视为一个大型单一群体。本研究将支持国家基因库的采样策略。
