摘要
Feed efficiency is an economically important trait in beef cattle. Net feed efficiency, measured as residual feed intake (RFI), is the difference between actual feed intake and the predicted feed intake required for maintenance and gain of the animal. SNPs that show associations with RFI may be useful quantitative trait nucleotides for marker-assisted selection. This study identified associations between SNPs underlying five RFI QTL on five bovine chromosomes (BTA2, 5, 10, 20 and 29) with measures of dry matter intake (DMI), RFI and feed conversion ratio (FCR) in beef cattle. Six SNPs were found to have effects on RFI (P < 0.05). The largest single SNP allele substitution effect for RFI was −0.25 kg/day located on BTA2. The combined effects of the SNPs found significant in this experiment explained 6.9% of the phenotypic variation of RFI. Not all the RFI SNPs showed associations with DMI and FCR even though these traits are highly correlated with RFI (r = 0.77 and r = 0.62 respectively). This shows that these SNPs may be affecting the underlying biological mechanisms of feed efficiency beyond feed intake control and weight gain efficiency. These SNPs can be used in marker-assisted selection but first it will be important to verify these effects in independent populations of cattle.
摘要译文
饲料效率是肉牛经济上重要的性状。净饲料效率，测量剩余采食量（RFI），是实际采食量和所需的维护和动物的增益的预测的饲料摄取量之间的差异。这显示出与RFI关联的SNP可能是有用的数量性状基因的核苷酸用于标记辅助选择。这项研究确定了单核苷酸多态性基本5 RFI QTL五个牛染色体（BTA2，5，10，20和29）与干物质采食量的措施之间的关联（DMI）RFI和肉牛饲料转化率（FCR）。六个SNP被发现有对RFI的影响（P25公斤/天位于BTA2。的单核苷酸多态性的联合作用发现在该实验显著解释6.9％的RFI的表型变异。并不是所有的RFI的SNP显示与关联DMI和饲料转化率，即使这些特质都是高度相关的RFI（r \x3d 0.77，并分别为R \x3d 0.62）。这表明，这些SNP可影响饲料效率超出采食量控制和体重增加效率的潜在的生物学机制。这些SNP可用于标记辅助的选择来使用，但首先核实在牛的独立种群这些影响将是非常重要的。
E. L. Sherman[1]; J. D. Nkrumah[1,2]; B. M. Murdoch[1] and S. S. Moore[1];. Identification of polymorphisms influencing feed intake and efficiency in beef cattle[J]. Animal Genetics, 2008,39(3): 225-231