Analysis of a New Zealand-specific no-cost option to reduce greenhouse gas emissions from dairy farms

This technical paper was produced by Ag Research for Motu. 

The Ministry for Primary Industries contracted Motu to identify and address barriers to adoption of apparent ‘no-cost’ greenhouse gas (GHG) mitigation options on farms in New Zealand. As part of this project, AgResearch has conducted an assessment of current farm practices and farm management GHG mitigation options that are apparently no-cost. A qualitative assessment of the extent to which these options could be both practical and adoptable, and remain no-cost, was made. This report provides a more quantitative analysis of the GHG mitigation potential of one of the options: a lower input dairy system with a lower stocking rate with cows of superior breeding worth (BW).

A lower input system that carries fewer cows of greater genetic merit (high breeding worth (BW) and lower stocking rate (SR) led to reductions in total GHG emissions and GHG emissions intensity, ranging between 2-16% and 3-14%, respectively, with the reduction potential generally increasing with increasing milksolids (MS) production. These systems were more complex to run, required advanced management skills across the farming system and the profitability relative to current systems was highly dependent on the milk pay-out price. These systems had co-benefits of reduced nitrogen emissions to water, however further research and development is required to enable these systems to be adopted and to remain highly productive and profitable with the added management complexity.