Feed management in ruminant production systems strongly affects agricultural greenhouse gas (GHG) emissions. Scientists from the LRG’s Feed and Nutrition Network (FNN) are working together on a major project, ‘Capturing Effects of Diet on Emissions from Ruminant Systems’ (CEDERS), to address these issues and build on the findings of the related FNN Global Network project. CEDERS currently involves European and New Zealand scientists. With funding from New Zealand, the project is being expanded under the GRA’s Enteric Fermentation Flagship to include data from Latin America and South East Asia.

The CEDERS project aims to:

  • Develop databases to evaluate dietary mitigation strategies (including digestion and excretion) and GHG emissions
  • Undertake experiments to fill high-priority knowledge gaps on dietary effects on ruminant manure emissions
  • Evaluate consequences of dietary mitigation measures on emissions on selected farm cases with a modelling platform
  • Improve farm accounting and national inventory methodologies to capture effects of dietary mitigation measures
  • Disseminate the implications of findings to end-users of GHG accounting and inventory.

Additional funding for Latin America and South East Asia will also:

  1. Identify region-specific feeds that could feasibly offer the most significant emissions reductions
  2. Develop Ym values for specific feeds suitable for inclusion in advanced national GHG inventories to help better quantify enteric methane emissions and, specifically, capture the impact of local diets and changes in diets on emissions

A Preliminary report on the applicability of process-oriented models for GHG reporting 2020, jointly authored by project leads; Ronaldo Vibart, Cecile de Klein, Arjan Jonker and Tony van der Weerden, has been completed as part of the CEDERS project and aims to:

  • Identify the most common on-farm GHG accounting tools used by the participating countries;
  • Explore the livestock GHG accounting approach used by these tools; and
  • Understand the potential benefits of adding further diet characteristics to on-farm GHG accounting tools for dairy cattle systems.

The focus is on methane emissions from enteric and manure management sources and nitrous oxide emissions from excreta and manure management sources.