The numbers of beef animals in New Zealand have increased markedly since 1960. In particular the number of animals (especially bulls) reared within the dairy industry for beef production has grown. Early research into aspects of intensive pasture-based beef production systems concentrated on high levels of pasture utilisation and beef production per ha. Farmers have adapted these results and systems and the carcass weight (CW) of bulls slaughtered now at 15-18 months of age have increased and often are over 300 kg CW. It is shown simplistically that profit/ ha will also increase with increasing CW and increased efficiency in use of feed within 1yr bull beef systems. In practice however, utilising more of the pasture dry matter (DM) grown and maintaining pasture quality are important issues. Two year bull systems are shown to be just as profitable as the more technically efficient 1yr bull system. Where beef production is carried out in conjunction with sheep production, especially on hill country, some commonly used benchmarks of technical and economic efficiency may be misleading with regard to overall system profitability and the contribution of various classes of beef animals. Keywords: beef animals, bulls, economic efficiency, feed efficiency, profitability
