Economic values for beef production traits from a herd level bioeconomic model

Abstract

A bioeconomic model of an integrated Canadian beef production system was developed to derive economic values for genetic improvement of multiple traits. The breeding objective was assumed to be profit maximization of the integrated enterprise. Sixteen input traits were identified as potentially influencing returns and costs in the system. These were mature size, direct and maternal calving ease (in heifers and cows separately), cow fertility, calf survival, cow survival, peak milk yield, residual post-weaning growth rate, residual feed intake in growing animals, residual feed intake in mature animals, residual slaughter weight and dressing percentage at constant backfat thickness, marbling and lean percentage. Most traits were defined to be functionally independent of each other. Thus, traits related to mature size were redefined as residual traits after accounting for the nonlinear relationships among mature size, growth and feed intake traits following mammalian size scaling rules. The base model, which incorporates average returns and costs under production and marketing systems typical of eastern Canada, is described. Economic values in the base model suggest that calf survival, fertility, residual feed intake, and dressing percentage are of primary economic importance in a purebreeding system. These traits also ranked highly in dam lines and (with the exception of fertility) in sire lines in terminal crossbreeding systems. Key words: Beef cattle, economic values, bioeconomic model