02741nam a2200241 a 450000100080000000500110000800800410001910000170006024501190007726001640019650003790036052015830073965000240232265000200234665300160236665300110238265300250239365300150241870000160243370000150244970000190246470000160248310618732021-03-31       2018    bl uuuu     u01u1 u    #d1 aPRAVIA, M.I.  aAssociation between feed efficiency and carcass and meat quality traits in Hereford steers.h[electronic resource]  aIn: Proceedings of the World Congress on Genetics Applied to Livestock Production, 11., Aotea Centre Auckland, New Zealand: WCGALP, ICAR, 11-16 feb 2018.c2018  aAcknowledgements: This work was supported by the Agencia Nacional de Investigación e Innovación (ANII) (grant RTS_1_2012_1_3489), Instituto Nacional de Investigación Agropecuaria (INIA), Sociedad de Criadores de Hereford (SCH), Instituto Nacional de Carnes (INAC), Instituto de Investigaciones Biológicas Clemente Estable (IIBCE) and Asociación Rural del Uruguay (ARU).  aSUMMARY. The association between residual feed intake (RFI) and growth, carcass and meat quality traits were investigated using 233 Hereford steers. Individual feed intake, body liveweight, average daily gain and ultrasound measurements were recorded during 70-d post-weaning period to calculate RFI. Steers were categorized into high efficient (<0.5 SD below the RFI mean; 72), medium (mid ± 0.5 SD; 85), and low efficient steers (>0.5 SD above the RFI mean; 76). After the feed intake test, steers grazed on sorghum pasture and oat with corn supplementation during summer and autumn and winter, respectively, until achieving the slaughter weight (with back fat thickness 6.35 mm). During the finishing phase, the efficient steers had some lighter weights (P<0.05) at the start of finishing but achieved the same slaughter weight (P<0.001). Average daily gains during finishing were similar among efficiency groups. No differences were found among groups on ultrasound measures except a slight difference on UBFAT at pre-slaughter between medium and lower efficient (P=0.009). No differences were found among RFI groups for any carcass or meat quality traits. Phenotypic correlations with RFI were close to zero for all traits. These results suggest that increasing feed efficiency by RFI does not lead to unfavorable effect on finishing performance, carcass and meat quality. Larger dataset will allow the estimation of genetic correlation among these traits and the prediction of genetic correlated responses. Keywords: Residual feed intake, beef cattle, growth, tenderness.  aALIMENTACION ANIMAL  aGANADO DE CARNE  aBeef cattle  aGrowth  aResidual feed intake  aTenderness1 aNAVAJAS, E.1 aMACEDO, F.1 aCLARIGET, J.M.1 aLUZARDO, S.