Chalebgwa A B, Monau P I, Raphaka K, Hadebe K, Kgwatalala P M, Nsoso S J
Department of Animal Sciences, Faculty of Animal and Veterinary Sciences, Botswana University of Agriculture and Natural Resources, Private Bag 0027, Gaborone 00000, Botswana.
Department of Animal Sciences, Faculty of Animal and Veterinary Sciences, Botswana University of Agriculture and Natural Resources, Private Bag 0027, Gaborone 00000, Botswana; Center for Bio-Economy, Botswana University of Agriculture and Natural Resources, Private Bag 0027, Gaborone 00000, Botswana.
Animal. 2025 Aug;19(8):101592. doi: 10.1016/j.animal.2025.101592. Epub 2025 Jul 2.
The Tswana goat, a key component of Botswana's livestock, is renowned for its resilience and adaptability to low-resource environments. The objective of this study was to use homozygosity (ROH) and supplementary methods (F, iHS, xp-EHH, Rsb) to identify selection signatures and inbreeding pattern of the indigenous Tswana goat. A total of 216 goats were used, that is, Tswana (n = 114) from three agroecological regions in Botswana and Boer (n = 102), a reference population from South Africa. After quality control, 216 animals and 49 732 single-nucleotide polymorphisms were available for analysis. Tswana goats exhibited an average ROH length of 2.20 Mb and 85.71 ROH per goat, while Boer goats had longer, fewer ROH, averaging 155.96 Mb and 3.14 ROH per goat. Tswana goats had a lower inbreeding coefficient (F = 0.08) compared to Boer goats (F = 0.13). Significant ROH hotspots were found on chromosomes 12, 6, and 5 in Tswana goats and on chromosomes 24, 14, 9, 8, and 6 in Boer goats, with 27 annotated genes identified. Multiple selection signature detection methods detected genes such as PUS7L, ADAMTS20, TWF1, PRICKLE1 YAF2 and GXYLTI. Key genes associated with reproductive fitness (ATP12A, RNF17), immune response (IL17D, PARP4), coat colour variation (ADAMTS20), and milk synthesis (TWF1) were highlighted in Tswana goats, reflecting adaptive responses to environmental pressures. The study provides insights into the genetic adaptations and historical breeding of Tswana goat. This knowledge is crucial for implementing effective conservation strategies and enhancing the resilience of indigenous goat populations. By prioritising the genetic study of these goats, Botswana can ensure the sustainability of its unique livestock resources, promoting both food security and rural development in the region.
茨瓦纳山羊是博茨瓦纳牲畜的重要组成部分，以其对资源匮乏环境的适应力和适应能力而闻名。本研究的目的是利用纯合性（ROH）和补充方法（F、iHS、xp-EHH、Rsb）来识别本土茨瓦纳山羊的选择特征和近亲繁殖模式。总共使用了216只山羊，即来自博茨瓦纳三个农业生态区的茨瓦纳山羊（n = 114）和来自南非的参考种群布尔山羊（n = 102）。经过质量控制后，有216只动物和49732个单核苷酸多态性可用于分析。茨瓦纳山羊的平均ROH长度为2.20 Mb，每只山羊有85.71个ROH，而布尔山羊的ROH更长、数量更少，平均每只山羊为155.96 Mb和有3.14个ROH。与布尔山羊（F = 0.13）相比，茨瓦纳山羊的近亲繁殖系数较低（F = 0.08）。在茨瓦纳山羊的12号、6号和5号染色体上以及布尔山羊的24号、14号、9号、8号和6号染色体上发现了显著的ROH热点，共鉴定出27个注释基因。多种选择特征检测方法检测到了PUS7L、ADAMTS20、TWF1、PRICKLE1、YAF2和GXYLTI等基因。在茨瓦纳山羊中突出显示了与繁殖适应性（ATP12A、RNF17）、免疫反应（IL17D、PARP4）、毛色变异（ADAMTS20）和乳汁合成（TWF1）相关的关键基因，反映了对环境压力的适应性反应。该研究为茨瓦纳山羊的遗传适应性和历史育种提供了见解。这些知识对于实施有效的保护策略和增强本土山羊种群的适应能力至关重要。通过优先开展这些山羊的遗传研究，博茨瓦纳可以确保其独特牲畜资源的可持续性，促进该地区的粮食安全和农村发展。
