Departamento de Zootecnia, Universidade Federal de Viçosa, 36570-000 Viçosa, MG, Brazil.
J Dairy Sci. 2011 Feb;94(2):971-80. doi: 10.3168/jds.2009-2970.
Fourteen Brazilian dairy Gyr sire families with 657 daughters were analyzed for quantitative trait loci (QTL) on chromosome 6 by using a daughter design for 5 economic traits: milk, fat, and protein production, fat and protein percentage. The cows and sires were genotyped for 27 microsatellites with average spacing between markers of 4.9 cM. In the analyses across 14 families, for the largest significant families, and within family, a QTL was located for milk yield and fat yield close to marker BMS2508 at the 5% chromosome-wide significance level across families and 1% chromosome-wide within families. For fat percentage, a QTL near DIK4482 was identified at the 5% chromosome-wide significance level when all families were analyzed together and at the 1% chromosome-wide significance level within the largest significant families. The different analyses yielded results that were generally consistent for milk yield, fat yield, and fat percentage. The order of the markers in the derived map was consistent with that in the consensus map. Some QTL and candidate genes in dairy cattle for milk production traits are probably preserved in Bos taurus and Bos indicus.
14 个巴西奶牛 Gyr 种公牛家系的 657 头女儿牛被用于分析第 6 号染色体上的数量性状基因座（QTL），采用的是针对 5 种经济性状（产奶量、乳脂率、乳蛋白率、脂肪量和蛋白量）的女儿设计。对牛和种公牛进行了 27 个微卫星的基因分型，标记间的平均间隔为 4.9cM。在跨 14 个家系的分析中，对于最大显著家系以及家系内，在跨家系 5%染色体水平显著和在家系内 1%染色体水平显著处，一个 QTL 被定位到了产奶量和乳脂产量上，靠近标记 BMS2508。对于乳脂率，当所有家系一起分析时，在跨家系 5%染色体水平显著和在家系内最大显著家系的 1%染色体水平显著处，在 DIK4482 附近检测到了一个 QTL。对于产奶量、乳脂产量和乳脂率，不同的分析结果基本一致。导出图谱中标记的顺序与共识图谱一致。在奶牛生产性状中，一些与 QTL 和候选基因有关的基因可能在牛属和印度野牛中得到了保存。
