Feed Additives and Methane Production

Why It Matters

Reducing ruminant methane with breeding and feed‑additive technologies enables Ireland to hit climate targets without sacrificing farm profitability.

Key Takeaways

• Agriculture generates ~40% of Ireland’s GHG, 75% methane.
• Methane is heritable; breeding low‑emission cattle must maintain performance.
• Feed additives like seaweed, nitrates, and lipids reduce rumen methane.
• Silage digestibility decline raises methane; high‑quality grass lowers emissions.
• Graange’s Methabate project proved additive safety for meat and milk.

Summary

The Chagaskk Signpost webinar, hosted by Mark Gibson and Kian Condan, examined feed‑additive strategies to curb methane emissions from Irish livestock. Researchers from Graange, including Emily Roskam and climate adviser Mave O’Hagen, presented the latest work on breeding, nutrition, and on‑farm additive testing.

Ireland’s agricultural sector accounts for roughly 40% of national greenhouse‑gas output, with methane comprising about 75% of that share. The presenters highlighted methane’s moderate heritability (0.2‑0.3) and warned that selecting solely for low emissions can inadvertently favor smaller, lower‑producing animals. Consequently, breeding programs now target methane yield per unit of dry‑matter intake. Parallelly, grass‑quality management—maintaining silage digestibility and optimal pre‑grazing sward height—was shown to influence emissions dramatically.

Data from Graange’s in‑vitro batch cultures and rumen simulation systems demonstrated that additives such as Bova‑3OP, nitrate‑based Sylve, marine seaweeds, lipids, and essential oils can cut methane output by up to 15% without harming animal performance. Field trials confirmed that high‑quality silage produced 308 g CH₄ day⁻¹ versus 357 g CH₄ day⁻¹ with lower‑quality silage, while grass‑clover mixes boosted intake and weight gain but also raised emissions proportionally. The Methabate project validated these additives for farm readiness and verified that meat and milk residues remain within safety limits.

The findings suggest Irish producers can achieve measurable emission reductions through a combined approach: selective breeding, precise feed‑intake monitoring, and deployment of vetted feed additives. Scaling these practices could help meet national climate commitments while preserving productivity and product quality, offering a competitive edge for Ireland’s dairy and beef sectors.

Original Description

Teagasc’s Emily Roskam, joined Cian Condon on the latest podcast version of the Signpost Series to discuss ‘Feed Additives and Methane Production’.

A questions and answers session took place at the end of the webinar which was facilitated by Meabh O’Hagan, Climate Action and Sustainability Advisor, Teagasc.

You can watch the webinar at:

https://youtu.be/hQYSU-mdaG0?si=946WastEuTTaqPY9

To register for future webinars go to:

https://www.teagasc.ie/corporate-events/sustainable-agriculture-webinars/

For more podcasts from the Signpost Series:

https://www.teagasc.ie/signpostpodcast/