Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: March 9, 2010
Publication Date: July 1, 2010
Citation: Sexten, A.K., Kuehn, L.A., Smith, T.P., Freetly, H.C., Snelling, W.M., Lindholm-Perry, A.K. 2010. A Region on BTA6 Is Associated with Feed Intake and Gain in Beef Cattle [abstract]. Journal of Animal Science. 88 (E-Supplement 2):185. Technical Abstract: Genetic selection for animals that require less feed while still achieving acceptable levels of production could result in substantial cost savings for cattle producers. The purpose of this study was to identify DNA markers with predictive merit for differences among cattle in feed intake and BW gain. Crossbred steers (n = 1,195) were fed a high-corn diet for 140 d and ADFI, residual feed intake (RFI), and ADG were measured. Steers were genotyped with the Illumina Bovine SNP50 BeadChip. An association analysis of these SNP on each trait was performed using MTDFREML, from which 14 SNP clustered in a 1.7Mb region at BTA6: 37.4 to 39.1 were identified as having significant association (P < 0.009) with one or more of the 3 traits. All statistical models included fixed effects of year and location; covariates of age, heterosis, and breed percentage; and a random polygenic effect. In order to develop markers with the maximum ability to discriminate favorable alleles and potentially identify the functional variation, 44 additional SNP, not present on the BeadChip, were identified in and around potential candidate genes in this chromosomal region. These new SNP were genotyped on the same animals and the statistical analysis program Mendel was used to test for association with feed intake and gain. Four markers located in a 90Kb region on BTA6 were significant for both ADFI and ADG. After correction for multiple testing, all markers remained significant for ADG (P </= 0.02) and 2 markers were significant for ADFI (P </= 0.01). These markers are located in a bovine gene that is homologous to a human gene that has been associated with skeletal frame size, thus providing a potential link between the observed bovine variation and growth-related traits of ADFI and ADG. Genetic markers predictive for feed intake and growth in this population of cattle may be useful for the identification and selection of animals that are more efficient, although potential impact of marker-assisted selection on all production traits will need to be assessed.