作者: J. D. Nkrumah , E. K. Okine , G. W. Mathison , K. Schmid , C. Li
DOI: 10.2527/2006.841145X
关键词:
摘要: Residual feed intake (RFI) is the difference between actual and expected of an animal based on its BW growth rate over a specified period. The biological mechanisms underlying variation in efficiency animals with similar are not well understood. This study determined relationship feedlot efficiency, performance, feeding behavior digestion energy partitioning 27 steers. steers were selected from total 306 their RFI following tests at University Alberta Kinsella Research Station. Selected ranked into high (RFI >0.5 SD above mean, n = 11), medium ± 0.5 below 8), low 0.10). was correlated daily methane production lost as (r 0.44; P < 0.05). Methane 28 24% less low-RFI compared high- medium-RFI animals, respectively. tended to be associated (P 0.10) apparent digestibilities DM -0.33) CP -0.34). DE -0.41; 0.05), ME -0.44; heat (HP; r 0.68; 0.001), retained (RE; -0.67; 0.001; values expressed kcal/kg BW). Feedlot partial 0.01) -0.55), 0.46), 0.49), HP -0.50), RE 0.62). With exception 0.37; conversion ratio unrelated traits considered study. Feeding duration digestibility -0.47), 0.51), -0.52), -0.60). These results have practical implications for selection that eat environmental sustainability beef production.