A GENOME SCAN FOR QTL AFFECTING GROWTH TRAITS IN BEEF CATTLE
BEEVER, JONATHAN E.(1), Yang Da(2), Harris A. Lewin(1)
1. University of Illinois, Department of Animal Sciences, 1201
W. Gregory Drive, Room 206, ERML, Urbana, IL 61801
2. Animal Improvement Programs Laboratory, USDA-ARS, Beltsville, Maryland 20705-2350
Eight paternal half-sib families were used to identify quantitative trait loci (QTL) affecting growth traits in beef cattle. Traits included birth weight (BW), adjusted weaning (AWW) and yearling weights (AYW), frame score (FRM), pelvic width (PEL) and scrotal circumference (SCT). A total of 207 genetic markers distributed among all 29 bovine autosomes were used for analyses. The average number of heterozygous markers per sire was 125. Statistical analyses were performed by single marker ANOVA and multiple marker maximum likelihood methods. Results indicate the presence of QTL candidates on chromosomes 6, 12, 18, 19, 21 and 23 that may affect one or more growth traits in beef cattle. The association of markers on BTA12 with AWW confirms the previously reported QTL for preweaning growth associated with bovine B erythrocyte antigen (Beever et al., J. Anim. Sci. 67:337-344, 1990).