|Neel, James - Jim|
|Felton, Eugene E D - West Virginia University|
|Duckett, Susan - Clemson University|
|Swecker Jr, William - Virginia Polytechnic Institution & State University|
Submitted to: Journal of Animal Science
Publication Type: Proceedings
Publication Acceptance Date: 3/15/2011
Publication Date: 7/11/2011
Citation: Neel, J.P., Felton, E., Duckett, S.K., Swecker Jr, W.S. 2011. Relationship between residual feed intake, performance, and carcass parameters of pasture finished cattle. Journal of Animal Science. 89(1):307-308.
Technical Abstract: In 2009 and 2010, Angus-crossbred steers (n = 39) were used to evaluate the relationship between residual feed intake (RFI), pasture-finishing performance and carcass parameters. During RFI determinations prior to pasture finishing initiation in mid-April, animals were fed an alfalfa hay cube diet. Animals were adapted to facilities and cubes for a 10 day period prior to intake measurements. Intakes were measured utilizing GrowSafe 6000 (GrowSafe Systems, Ltd., Airdrie, Alberta, Canada) feeding nodes (2009 = 30d; 2010 = 56d) for individual RFI classification of animals. Upon classification, animals were pasture finished on mixed-species pasture until harvest and carcass data collection in early November of each year (338 +/- 41kg initial BW; 500 +/- 40 kg final BW). During pasture finishing animals had an ADG of 0.81 +/- 0.12 kg. Mean carcass measurements were: hot carcass weight (HCW) 260 +/- 24 kg, fat thickness (FT) 0.445 +/- 0.177 cm, ribeye area (REA) 67.4 +/- 7.3 cm2, KPH 1.1 +/- 0.4%, yield grade (YG) 2.0 +/- 0.4, and marbling score (MS; 400-500 = slight) 477 +/- 62. Pearson correlation coefficients were utilized to assess RFI relationship with performance and carcass measurements. Residual feed intake was negatively (P < 0.01) correlated with ADG (r = -0.42), and tended (P = 0.086) to be positively correlated with KPH (r = 0.28). Residual feed intake was not correlated with initial or final BW, HCW, FT, REA, YG, or MS. Correlations with ADG and KPH need further investigation to determine impact on pasture finishing systems.