Tactical decisions of concentrate level, slaughter age and carcass weight of bulls of five beef breeds under Norwegian conditions

Abstract

Beef production based on suckler cow breeds is a relatively new production system in Norway as in most Nordic countries. To ensure the continuation of this production, profitable management practices designed for Norwegian conditions have to be established. Thus a simulation model was developed that integrates the daily feed intake, the daily live weight (LW) gain, silage net energy concentration for beef production (feed units beef (FUb) kg?1 dry matter) and price, concentrate level and price, and carcass price for bulls of the country's five most common beef breeds. In this work the model was combined with production statistics to find general recommendations in the finishing of beef bulls under Norwegian conditions. Among all the five breeds the Limousin bulls had the highest estimated mean daily return and the Hereford bulls the lowest estimated mean daily return from 20 g concentrate kg?1 LW0.75 for the 940 FUb kg?1 silage dry matter, and from 40 g concentrate kg?1 LW0.75 for the 800 FUb kg?1 silage dry matter. Our estimated optimal slaughter ages and carcass weights shows that it pays to more intensively feed during the finishing period for all five breeds. Current farming practice in Norway for the five major breeds studied is that slaughter age is at least two months later with lighter carcass weights than the results expected from following our model estimated recommendations.