摘要
Selecting beef cattle which metabolically are more efficient at converting feed into gain or body weight maintenance is one way to reduce feed cost in beef production. Residual feed intake (RFI) is one trait used to identify animals which are metabolically feed efficient or inefficient. Trials in the current study investigated whether animal RFI varies between trials conducted at two different stages of maturity and the influence on progeny feed efficiency when sires and dams of known RFI phenotypes are mated. We further investigated whether RFI measured postweaning or later in maturity more accurately predicted progeny feed efficiency in addition to whether ribeye area and body composition varied between steers from either RFI- or RFI+ dams. Reranking in RFI of animals did occur between trials, however; RFI phenotype was correlated (rp = 0.54; P [less than] 0.01) between postweaning and mature trials indicating animals identified as feed efficient or inefficient remain feed efficient or inefficient further into maturity. More efficiently mated RFI- sires and dams produced heifer and steer progeny with higher feed efficiencies (P [less than] 0.05; P [less than] 0.10, respectively) with no difference in average daily gain (P = 0.52) in comparison to progeny from RFI+ sires and dams. Postweaning dam RFI phenotype showed stronger correlations to progeny RFI phenotype (rp = 0.60; P [less than] 0.05) while steers from RFI- dams tended (P [less than] 0.10) to have larger developments in ribeye area with no variation (P [greater than] 0.10) in body composition to steers from RFI+ dams. Selection upon RFI is an accurate trait to select upon to improve herd feed efficiency as well as increase profitability in beef production.
摘要译文
选择牛肉牛在将饲料转换为增益或体重维护时更有效，是降低牛肉生产饲料成本的一种方法。残留饲料进料（RFI）是一种用于识别代谢饲料效率或低效的动物的特征。目前研究中的试验研究了动物RFI是否在两种不同的成熟阶段进行的试验之间变化以及当已知RFI表型的轿车和坝时对后代饲料效率的影响。除了从RFI或RFI +坝的操纵器之间变化之外，还进一步研究了RFI在成熟的后期或后来的成熟预测的后代饲料效率。然而，在试验之间发生了在动物的RFI中进行重演; RFI表型相关（RP = 0.54;在切换和成熟试验之间的p [少于] 0.01）表明鉴定为饲料有效或低效的动物进一步饲料效率或低效进一步成熟。更有效地交配的RFI-和水坝产生的小母牛和转向后代，饲料效率较高（P [小于] 0.05;与来自RFI + Sires和水坝的后代的平均每日增益（P = 0.52）没有差异，与来自RFI + Sires和坝体的后期没有差异。切换坝RFI表型显示与后代RFI表型的相关性更强（RP = 0.60; P [少于] 0.05），而来自RFI的操纵器（P [小于] 0.10）在Ribeye区域中具有较大的发育，没有变化（P [大于] 0.10），对来自RFI +坝的操纵器。选择RFI是一种准确的特征，可以选择提高畜群饲料效率，并提高牛肉生产中的盈利能力。
Minton, Nicholas Oliver. Improvement of feed efficiency in beef cattle through selection upon residual feed intake (RFI)[D]. US: University of Missouri-Columbia, 2010