Live weight accounting for beef cow management

Abstract

Calculation and use of annual live weight production of a group of beef cattle, ie, net harvest of live weight from their grazing area over a year, which is a primary beef cattle business measure directly indicating income, is limited in practice because it is not well understood and there is generally insufficient record keeping to achieve it. This concept paper introduces live weight production from extensively-managed breeding cows grazing pastures in a novel way termed ‘live weight accounting’. Live weight production and its calculation and expression as a function of both animal and land units is introduced. Division by the average live weight of the grazing cattle over a year to produce a live weight production ratio, indicative of efficiency of conversion of available pasture to live weight, is then presented. Live weight accounting is based on the principles that cows can extract nutrition from a pasture for the combined annual live weight production of themselves and their calf, and that annual weaner production equates to yearling growth in the same situation. Applied use of these measures is proposed. Large variation in production and efficiency occurs within and between cattle management groups, indicating opportunity to improve in many situations by focusing on multiple putative risk factors, especially pasture utilisation and weaning management. Performance of breeding cattle, primarily pregnancy and survival and growth of cows and calves, can each be altered to regulate production. Live weight accounting is a novel practical concept that can be used to conceptualise and manage beef business analyses and decision making. The principles of live weight accounting are applicable to all beef systems globally. Its application is discussed for weaning, supplementation, heifer mating, first-lactation cow management, selection and culling in breeding herds. In addition, it can be used for application of steer research outcomes to breeding cattle management and for managing climate variation.