GxE for beef cattle breeding objectives as a consequence of differences in cow feed cost

The presence of genotype by environment interactions (GxE) affects the decisions made by livestock producers when selecting breeding animals. Studies have traditionally focussed on selection criteria, and on a single trait basis, with most finding little evidence of GxE. This study demonstrates that substantial GxE occurs for the beef cattle breeding objective. When the length of the feeding period or cow feed price varies, or they vary in combination, the correlations between sire rankings decrease. Ignoring the occurrence of this GxE in selection risks compromising commercial production system profitability.