Smetko Anamarija, Soudre Albert, Silbermayr Katja, Müller Simone, Brem Gottfried, Hanotte Olivier, Boettcher Paul J, Stella Alessandra, Mészáros Gábor, Wurzinger Maria, Curik Ino, Müller Mathias, Burgstaller Jörg, Sölkner Johann
Division of Livestock Sciences, Department of Sustainable Agricultural Systems, BOKU-University of Natural Resources and Life Sciences Vienna Vienna, Austria ; Croatian Agricultural Agency Zagreb, Croatia.
Division of Livestock Sciences, Department of Sustainable Agricultural Systems, BOKU-University of Natural Resources and Life Sciences Vienna Vienna, Austria ; Ecole Normale Supérieure, Université de Koudougou Koudougou, Burkina Faso.
Front Genet. 2015 Apr 21;6:137. doi: 10.3389/fgene.2015.00137. eCollection 2015.
Trypanosomosis is a serious cause of reduction in productivity of cattle in tsetse-fly infested areas. Baoule and other local Taurine cattle breeds in Burkina Faso are trypanotolerant. Zebuine cattle, which are also kept there are susceptible to trypanosomosis but bigger in body size. Farmers have continuously been intercrossing Baoule and Zebu animals to increase production and disease tolerance. The aim of this study was to compare levels of zebuine and taurine admixture in genomic regions potentially involved in trypanotolerance with background admixture of composites to identify differences in allelic frequencies of tolerant and non-tolerant animals. The study was conducted on 214 animals (90 Baoule, 90 Zebu, and 34 composites), genotyped with 25 microsatellites across the genome and with 155 SNPs in 23 candidate regions. Degrees of admixture of composites were analyzed for microsatellite and SNP data separately. Average Baoule admixture based on microsatellites across the genomes of the Baoule- Zebu composites was 0.31, which was smaller than the average Baoule admixture in the trypanosomosis candidate regions of 0.37 (P = 0.15). Fixation index F ST measured in the overall genome based on microsatellites or with SNPs from candidate regions indicates strong differentiation between breeds. Nine out of 23 regions had F ST ≥ 0.20 calculated from haplotypes or individual SNPs. The levels of admixture were significantly different from background admixture, as revealed by microsatellite data, for six out of the nine regions. Five out of the six regions showed an excess of Baoule ancestry. Information about best levels of breed composition would be useful for future breeding ctivities, aiming at trypanotolerant animals with higher productive capacity.
锥虫病是采采蝇肆虐地区牛群生产力下降的一个重要原因。布基纳法索的巴乌莱牛和其他当地瘤牛品种具有锥虫耐受性。当地饲养的瘤牛虽然易感染锥虫病，但体型较大。农民们一直在让巴乌莱牛和瘤牛杂交，以提高产量和疾病耐受性。本研究的目的是比较可能与锥虫耐受性相关的基因组区域中瘤牛和瘤牛混合水平与杂交后代的背景混合水平，以确定耐受性和非耐受性动物等位基因频率的差异。该研究对214头动物（90头巴乌莱牛、90头瘤牛和34头杂交后代）进行了基因分型，使用了全基因组的25个微卫星标记以及23个候选区域的155个单核苷酸多态性（SNP）。分别对微卫星和SNP数据的杂交后代混合程度进行了分析。基于巴乌莱牛-瘤牛杂交后代全基因组微卫星标记计算的平均巴乌莱牛混合比例为0.31，低于锥虫病候选区域的平均巴乌莱牛混合比例0.37（P = 0.15）。基于微卫星标记或候选区域SNP计算的全基因组固定指数FST表明各品种之间存在强烈分化。从单倍型或单个SNP计算得出，23个区域中有9个区域的FST≥0.20。微卫星数据显示，这9个区域中有6个区域的混合水平与背景混合水平存在显著差异。这6个区域中有5个区域显示巴乌莱牛血统过剩。了解最佳品种组成水平将有助于未来的育种活动，培育出具有更高生产能力的锥虫耐受性动物。
