BACKGROUND Reproductive performance is critical for efficient swine production. Recent results indicated that vulva size (VS) may be predictive of reproductive performance in sows. Study objectives were to estimate genetic parameters, identify genomic regions associated, and estimate genomic prediction accuracies (GPA) for VS traits. RESULTS Heritability estimates of VS traits, vulva area (VA), height (VH), and width (VW) measurements, were moderately to highly heritable in Yorkshire, with 0.46 ± 0.10, 0.55 ± 0.10, 0.31 ± 0.09, respectively, whereas these estimates were low to moderate in Landrace, with 0.16 ± 0.09, 0.24 ± 0.11, and 0.08 ± 0.06, respectively. Genetic correlations within VS traits were very high for both breeds, with the lowest of 0.67 ± 0.29 for VH and VW for Landrace. Genome-wide association studies (GWAS) for Landrace, reveled genomic region associated with VS traits on Sus scrofa chromosome (SSC) 2 (154-157 Mb), 7 (107-110 Mb), 8 (4-6 Mb), and 10 (8-19 Mb). For Yorkshire, genomic regions on SSC 1 (87-91 and 282-287 Mb) and 5 (67 Mb) were identified. All regions explained at least 3.4% of the genetic variance. Accuracies of genomic prediction were moderate in Landrace, ranging from 0.30 (VH) to 0.61 (VA), and lower for Yorkshire, with 0.07 (VW) to 0.11 (VH). Between-breed and multi-breed genomic prediction accuracies were low. CONCLUSIONS Our findings suggest that VS traits are heritable in Landrace and Yorkshire gilts. Genomic analyses show that major QTL control these traits, and they differ between breed. Genomic information can be used to increase genetic gains for these traits in gilts. Additional research must be done to validate the GWAS and genomic prediction results reported in our study.

中文翻译：

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约克夏母猪和长白母猪外阴大小性状的遗传和基因组特征。


背景技术繁殖性能对于猪的高效生产至关重要。最近的结果表明，外阴尺寸（VS）可以预测母猪的繁殖性能。研究目标是估计遗传参数，识别相关基因组区域，并估计 VS 性状的基因组预测准确性 (GPA)。结果 VS 性状、外阴面积 (VA)、高度 (VH) 和宽度 (VW) 测量值的遗传力估计在约克郡具有中等到高度遗传性，分别为 0.46 ± 0.10、0.55 ± 0.10、0.31 ± 0.09，而这些长白品种的估计值为低至中等，分别为 0.16 ± 0.09、0.24 ± 0.11 和 0.08 ± 0.06。两个品种的 VS 性状内的遗传相关性都非常高，长白品种的 VH 和 VW 的遗传相关性最低，为 0.67 ± 0.29。长白品种的全基因组关联研究 (GWAS)，揭示了与野猪染色体 (SSC) 2 (154-157 Mb)、7 (107-110 Mb)、8 (4-6 Mb) 和 VS 性状相关的基因组区域10（8-19 MB）。对于约克郡，鉴定出了 SSC 1（87-91 和 282-287 Mb）和 5（67 Mb）上的基因组区域。所有区域至少解释了 3.4% 的遗传变异。长白猪的基因组预测准确度中等，范围为 0.30 (VH) 至 0.61 (VA)，而约克夏则较低，范围为 0.07 (VW) 至 0.11 (VH)。品种间和多品种基因组预测的准确性较低。结论 我们的研究结果表明，长白猪和约克夏后备母猪的 VS 性状是可遗传的。基因组分析表明，主要的 QTL 控制着这些性状，并且它们在品种之间存在差异。基因组信息可用于增加后备母猪这些性状的遗传增益。必须进行额外的研究来验证我们研究中报告的 GWAS 和基因组预测结果。