Teagasc

Signpost Series: Feed Additives and Methane Production

The Signpost webinar focused on feed additives and other strategies to curb methane emissions from Irish livestock, featuring research officer Emily Roskam and climate adviser Mave Hagen. The session highlighted that agriculture accounts for roughly 40% of Ireland’s greenhouse‑gas output, with methane representing about three‑quarters of that share, primarily from rumen fermentation. Key insights included the heritability of methane production (0.2‑0.3), the need to select for methane yield rather than absolute emissions, and the impact of diet and pasture management on methane output. Grange’s in‑vitro and rumen simulation facilities enable rapid screening of additives—such as seaweed extracts, lipids, nitrates, and essential oils—while measuring digestibility and animal performance. Studies showed that silage quality, grazing height, and grass‑clover mixes affect both intake and methane, with higher‑quality forage reducing emissions and improving weight gain. Notable examples cited were ICBF’s 2024 breeding values identifying bulls that emit 9‑10 g less methane per day, and field trials where grass‑clover pastures increased daily live‑weight gain by up to 23 kg without harming methane mitigation when managed correctly. A large Methabate project screened dozens of additives, pinpointing several farm‑ready candidates for pasture‑based systems. The implications are clear: integrating genetic selection with targeted feed additives and optimized pasture management can deliver measurable methane reductions while sustaining or enhancing productivity. This creates a pathway for Irish producers to meet tightening emissions regulations, access carbon‑credit markets, and improve profitability through more efficient feed use.