Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: May 19, 2011
Publication Date: July 1, 2011
Citation: Lindholm-Perry, A.K., Kuehn, L.A., Smith, T.P., Snelling, W.M., Freetly, H.C. 2011. Genetic markers in bovine chromosome 14 are significant for residual feed intake in steers. Journal of Animal Science. 89(E-Suppl. 1):422-423. 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 for traits associated with feed efficiency. Crossbred steers (n = 1,195) were fed a high-corn diet for 140 d and average daily feed intake (ADFI), ADG, and residual feed intake (RFI) phenotypes were obtained. RFI was defined from the regression of ADFI on ADG and mid-metabolic BW. These animals were genotyped with the Illumina Bovine SNP50 BeadChip and an association analysis of these single nucleotide polymorphisms (SNP) was performed. A 1.6 Mb region at BTA14: 22.3 to 23.9 was identified as having significant association (nominal P = 0.04 to 0.0006) with RFI. In order to develop markers with the maximum ability to discriminate favorable alleles, 70 additional SNP, not present on the BeadChip, were genotyped within this chromosomal region. These new SNP were genotyped on the same animals and tested for association with ADFI, ADG, and RFI. The statistical model included fixed effects of year and location; covariates of age, heterosis, and breed percentage; and a random polygenic effect. Ten markers were nominally significant within this region for RFI, the most significant of these were clustered between 23.3 to 23.5 Mb. After conservative correction for multiple testing, one marker at 23.30 Mb remained significant. Many of these markers were also significant for ADG, although none were significant after correction. Alleles with positive effects on ADG correspond to negative effects on RFI, suggesting a marker effect of increased growth without increased feed intake. These markers may be useful as prediction tools for animals that utilize feed more efficiently; however, potential impact of these markers on additional production traits will need to be assessed.