2009-Sherman_et_al - Fine mapping quantitative trait loci...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
E. L. Sherman, J. D. Nkrumah, C. Li, R. Bartusiak, B. Murdoch and S. S. Moore Fine mapping quantitative trait loci for feed intake and feed efficiency in beef cattle doi: 10.2527/jas.2008-0876 originally published online Sep 12, 2008; 2009.87:37-45. J Anim Sci http://jas.fass.org/cgi/content/full/87/1/37 the World Wide Web at: The online version of this article, along with updated information and services, is located on www.asas.org by on October 22, 2010. jas.fass.org Downloaded from
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
ABSTRACT: Feed intake and feed efficiency are eco- nomically important traits in beef cattle because feed is the greatest variable cost in production. Feed efficiency can be measured as feed conversion ratio (FCR, intake per unit gain) or residual feed intake (RFI, measured as DMI corrected for BW and growth rate, and sometimes a measure of body composition, usually carcass fatness, RFI bf ). The goal of this study was to fine map QTL for these traits in beef cattle using 2,194 markers on 24 autosomes. The animals used were from 20 half-sib families originating from Angus, Charolais, and Univer- sity of Alberta Hybrid bulls. A mixed model with ran- dom sire and fixed QTL effect nested within sire was used to test each location (cM) along the chromosomes. Threshold levels were determined at the chromosome and genome levels using 20,000 permutations. In to- tal, 4 QTL exceeded the genome-wise threshold of P < 0.001, 3 exceeded at P < 0.01, 17 at P < 0.05, and 30 achieved significance at the chromosome-wise thresh- old level (at least P < 0.05). No QTL were detected on BTA 8, 16, and 27 above the 5% chromosome-wise significance threshold for any of the traits. Nineteen chromosomes contained RFI QTL significant at the chromosome-wise level. The RFI bf QTL results were generally similar to those of RFI, the positions being similar, but occasionally differing in the level of signifi- cance. Compared with RFI, fewer QTL were detected for both FCR and DMI, 12 and 4 QTL, respectively, at the genome-wise thresholds. Some chromosomes con- tained FCR QTL, but not RFI QTL, but all DMI QTL were on chromosomes where RFI QTL were detected. The most significant QTL for RFI was located on BTA 3 at 82 cM ( P = 7.60 × 10 −5 ), for FCR on BTA 24 at 59 cM ( P = 0.0002), and for DMI on BTA 7 at 54 cM ( P = 1.38 × 10 −5 ). The RFI QTL that showed the most con- sistent results with previous RFI QTL mapping studies were on BTA 1, 7, 18, and 19. The identification of these QTL provides a starting point to identify genes affecting feed intake and efficiency for use in marker- assisted selection and management. Key words: beef cattle, feed efficiency, feed intake, quantitative trait loci, residual feed intake ©2009 American Society of Animal Science. All rights reserved. J. Anim. Sci. 2009. 87:37–45 doi:10.2527/jas.2008-0876 INTRODUCTION Feed efficiency and intake are economically important traits to beef cattle producers because feed is the great- est variable cost in production (Arthur et al., 2004). It
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/26/2012 for the course ECON 2272 taught by Professor Gay during the Spring '08 term at Birmingham-Southern College.

Page1 / 11

2009-Sherman_et_al - Fine mapping quantitative trait loci...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online