Energy and economic efficiency in grazing dairy systems under alternative intensification strategies

Abstract The intensification of dairy systems, or the process of increasing milk productivity per unit of land area, can be achieved through various strategies. However, it is debated whether intensification is associated with increased economic and/or environmental efficiency. The aim of this study was to identify alternative intensification strategies for grazing dairy systems and evaluate their economic and energy efficiency. A model for calculating energy inputs and outputs was applied to 30 dairy farms with reliable production and economic records in Uruguay, spanning a wide range of farm features. Milk productivity averaged 3819 l.ha −1  year −1 (ranging from 1512 to 6942), intake of concentrate averaged 0.25 kg l −1 of milk (ranging from 0.03 to 0.38), fossil energy use averaged 3.96 MJ kg −1 (ranging from 1.9 to 9.1) and farm net income averaged 317 U$D ha −1  year −1 (ranging from 136 to 748). Using a numerical classification procedure, four farm clusters that represent different technological, production, and efficiency situations for grazing dairy farms were identified, associated with the differential use of pastures and concentrates. Although increasing used of concentrates in diets was associated with higher milk productivity, and sometimes higher economic performance, it was consistently negatively associated with energy efficiency. Dairy farms with a higher proportion of pasture consumption achieved higher efficiency of utilization of feed concentrates (higher kg milk/kg concentrate) and thus used less fossil energy per liter of milk. These results suggest that sustainable intensification of grazing dairy systems should rely on efficient utilization of pastures rather than just increasing concentrate intake.