The effects of cow and (or) calf genotype for two candidate gene markers [growth hormone (GH) and insulin-like growth factor-I (IGF-1) genes] on production traits were evaluated in a beef cattle herd. The GH polymorphism is located in exon V of the GH gene and is associated with a leucine/valine amino acid substitution. The IGF-1 polymorphism is located in the 5' flanking region of the IGF-1 gene. Cow GH genotype was not significantly associated with cow production traits (milk yield, average weight, hip height, and condition score) or progeny weight at birth or weaning. The regression of weaning weight on number of valine (versus leucine) alleles in the calf GH genotype indicated a possible association with calf weaning weight, although genotype least-squares means were not significantly different. Calf GH genotype tended to be associated with carcass cutability, but not with birth weight, carcass weight, or marbling score. Cow IGF-1 genotype was significantly associated with estimated milk yield and progeny weaning weight, but not with cow size traits or cow body condition score. Calf IGF-1 genotype was not significantly associated with any of the calf growth or carcass traits evaluated.
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South Dakota State University
Copyright © 2000 South Dakota State University
Marshall, D. M. and Kim, J., "Associations of Beef Production Traits with Polymorphisms in the Growth Hormone Gene and Insulin-Like Growth Factor-1 Gene" (2000). South Dakota Beef Report, 2000. 12.