Comparing risk for different dairy farm management systems in Taranaki using the Dexcel Whole Farm Model

Abstract

The approach was to use the Whole Farm Model (WFM) and Taranaki climate to compare a conventional, twice-a-day milking farm system with variations of once-a-day (OAD) milking and high-input systems. The aim was to compare production, return on assets (ROA) and risk as affected by climate and price variability. Simulations were run over 9 different climate years (1995/1996 - 2003/2004). The high-input system had the highest production (1333 kg milksolids (MS)/ ha) and highest ROA (10.8%), with variability thereof dampened by a feed buffer of higher quantity and quality that existed because of higher pasture yields (15.8 t dry matter (DM)/ha with 200 kg nitrogen (N)/ha vs. 13.5 t DM/ha with 105 kg N/ha for the other two systems), maize silage and grazing-off. The high-input system was followed by the OAD and conventional systems in terms of production (1068 and 975 kg MS/ha respectively) and ROA (9.8% and 9.2% respectively). Both OAD and conventional systems showed risk values nominally lower than high-input, but both these systems were more severely affected by climatic var iability, which lowered the average return and increased the risk relative to the return. Keywords: climate var iability, high input farming, once-a-day milking, return on assets