Production and profit of current and future dairy systems using differing nitrogen leaching mitigation methods: the Pastoral 21 experience in Waikato

The aim of the study was to determine if existing technologies could reduce nitrate leaching by 50%; while maintaining high levels of milk production and profitability. One farmlet, typical of the Waikato ('CURRENT') was stocked at 3.2 cows/ha and compared with a farmlet stocked at 2.6 cows/ha ('FUTURE'), focusing on higher cow production through the use of higher genetic merit cows, lower N fertiliser usage and removing cows from pasture (to a stand-off pad) during critical N leaching periods. The mitigation methods employed on the FUTURE farmlet reduced N leaching by 43% but meant the FUTURE farmlet was more expensive to run than the CURRENT (Control) farmlet. Although cows on the FUTURE farmlet each produced 68 kg more milksolids, production per hectare was 50 kg lower. Thus, the FUTURE farmlet yielded on average $279/ha/yr less profit than the CURRENT farmlet.