Relationship between Beef Heifer Residual Feed Intake and Productivity as Cows

Abstract Text: The effect of heifer residual feed intake (RFI) (n=451) on subsequent lifetime productivity as cows (mating opportunities=1081) was measured over an 8-year period (2005-2013) at Lacombe, Alberta, Canada. Most probable producing ability for birth weight (MPPAbw) and weaning weight (MPPAww) were calculated as measures of cow productivity.  RFI was negatively correlated (P=0.02) to MPPAbw, but was not significant when RFI was adjusted for backfat thickness (P=0.08) or backfat thickness and feeding activity (P=0.10).  No significant correlations were found between RFI or adjusted RFI and MPPAww (P=0.64).  Lifetime productivity (LTP) was calculated for cows culled from the herd (n=108) over the eight-year period.  RFI and LTP were not correlated (P=0.10).  Selection for feed efficient, low RFI replacement heifers appears to have no impact on their productivity as cows. 

Keywords:

Beef Cattle

Residual Feed Intake

Cow productivity