Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/6/2000
Publication Date: 7/6/2000
Citation: THRIFT, F.A., BROWN, M.A., THRIFT, T.A. A REVIEW OF GENOTYPE X ENVIRONMENT INTERACTION STUDIES CONDUCTED IN THE U.S. INVOLVING CATTLE VARYING IN PERCENTAGE BOS INDICUS INHERITANCE. PROFESSIONAL ANIMAL SCIENTIST. 2000. v. 16. p. 149-158.
Interpretive Summary: Reproductive, preweaning, and postweaning performance of beef cattle are influenced by the genetics of the cattle and the production environment. Moreover, there is the potential for the performance of different genetic types to depend on the production environment. This is called genotype x environment interaction. A review of 44 research studies spanning 10 different states was done to summarize the status of genotype x environmen interactions involving Brahman genetics and either geographic location or management within a location. It was apparent from the review that performance differences among varying percentage Brahman cattle depend on the production environment. Consequently, careful consideration should be given to matching the genetics of cattle to production environment to achieve optimum performance.
Technical Abstract: A review of 44 studies spanning 10 different states was done to summarize the status of genotype x environment interactions involving Brahman genetics and either geographic location or management within a location. States involved included FL, LA, AR, TX, OK, MO, TN, KS, NE, and CO. Genotypes in the studies included varying percentages of Bos indicus breeding ranging from 100 to 0%. Geographic environments included subtropical vs. temperate, subtropical vs. subtropical, and semiarid vs. humid. Management environments within locations included differential grazing pressures, differential forage programs, spring vs. fall calving, differential calving ages at first calf, variable postweaning feed energy levels, and variable feedlot/carcass management scenarios. Genotype x location and genotype x management interactions were evident (P<.10) for reproductive and preweaning traits with the interactions being differences of magnitude rather than rank. There was some evidence of genotype x environment interactions in postweaning performance and carcass traits (P<.10) but these were less prevalent and less consistent than interactions observed in preweaning performance. The results from this review suggest that potential for genotype x environment interaction should be carefully considered when developing breeding plans for calf production. Additionally, since the importance of such interactions is well-documented, future research should emphasize metabolic and physiologic reasons for such interactions.