The beef breeding herd: options for using winter feed most productively

Abstract

A spreadsheet model has been developed to allow a comparison of policies for beef breeding cows. The criterion for comparison is the kg of calf weaned per kg of winterfeed required i.e. efficiency. The model allows adjustment in number of animals wintered so that all policies have the same winter feed requirement. Policies which favour higher efficiencies include: timing mean calving date at the end of the winter, using breeds of bull with high growth rate and high survival rate progeny, older rather than younger herd age structures. and wintering only pregnant heifers and cows after pregnancy diagnosis. The most scope for improving efficiency is in herd age structure while the least scope is in calving date. The analysis demonstrates that that the most efficient options are a combination of policies. The best combination is about 26% more efficient than the worst combination. National beef herd statistics are required to assess the likely impact of changes on the industry. Keywords: beef cows, weaning weight, herd age structure, pregnancy diagnosis, feed requirements, time of calving, terminal sires