Cooper T A, Wiggans G R, Null D J, Hutchison J L, Cole J B
Animal Improvement Programs Laboratory, Agricultural Research Service, US Department of Agriculture (USDA), Beltsville, MD 20705-2350.
Animal Improvement Programs Laboratory, Agricultural Research Service, US Department of Agriculture (USDA), Beltsville, MD 20705-2350.
J Dairy Sci. 2014;97(6):3878-82. doi: 10.3168/jds.2013-7427. Epub 2014 Mar 27.
Genomic evaluations of dairy cattle in the United States have been available for Brown Swiss, Holsteins, and Jerseys since 2009. As of January 2013, 1,023 Ayrshires had genotypes in the North American database. Evaluation accuracy was assessed using genomic evaluations based on 646 bulls with 2008 traditional evaluations to predict daughter performance of up to 180 bulls in 2012. Mean gain in reliability over parent average for all traits was 8.2 percentage points. The highest gains were for protein yield (16.9 percentage points), milk yield (16.6 percentage points), and stature (16.2 percentage points). Twelve single nucleotide polymorphisms were useful for Ayrshire breed determination. Fewer breed-determining SNP were available for Ayrshires than for Holsteins, Jerseys, and Brown Swiss because of the similarity of Ayrshires and Holsteins. A haplotype that affects fertility was identified on chromosome 17 and traces back in the genotyped population to the bull Selwood Betty's Commander (born in 1953). The haplotype carrier frequency for genotyped Ayrshires was 26.1%. Sire conception rate was decreased by 4.3 ± 2.5 percentage points for carriers of the haplotype as determined by 618 matings of carrier sire by carrier maternal grandsire. Genomic evaluations for Ayrshires were officially implemented in the United States in April 2013.
自2009年以来，美国已对瑞士褐牛、荷斯坦奶牛和泽西奶牛进行了基因组评估。截至2013年1月，北美数据库中有1023头爱尔夏牛的基因型。利用基于646头公牛的基因组评估（这些公牛有2008年的传统评估数据）来预测2012年多达180头公牛的女儿的生产性能，以此评估评估准确性。所有性状相对于亲本平均值的可靠性平均提高了8.2个百分点。提高幅度最大的是蛋白质产量（16.9个百分点）、产奶量（16.6个百分点）和体高（16.2个百分点）。12个单核苷酸多态性可用于爱尔夏牛品种鉴定。由于爱尔夏牛与荷斯坦奶牛相似，可用于爱尔夏牛品种鉴定的单核苷酸多态性比荷斯坦奶牛、泽西奶牛和瑞士褐牛的少。在17号染色体上鉴定出一个影响繁殖力的单倍型，在已分型群体中可追溯到公牛塞尔伍德·贝蒂的指挥官（出生于1953年）。已分型爱尔夏牛的单倍型携带频率为26.1%。通过携带该单倍型的父本与携带该单倍型的母系祖父的618次交配确定，该单倍型携带者的父本受胎率降低了4.3±2.5个百分点。2013年4月，美国正式实施了爱尔夏牛的基因组评估。
