Understanding and reducing greenhouse gas (GHG) emissions begins with access to reliable, real-world data. This principle sits at the heart of Newcastle University’s contribution to the UK Dairy Carbon Network (UK-DCN) project, drawing on its development of a novel ‘sniffer’ sensor system to monitor methane emissions from dairy cows. Dr Hannah Davis, Lecturer in Ruminant Nutrition & Pasture Management at Newcastle University, explains the approach.
Dr Davis notes that farmers regularly report that there is an expectation for them to demonstrate progress on emissions reduction while relying on calculators based on assumptions rather than site-specific data. To build trust and support meaningful change, they emphasise the need for evidence that is credible, accessible and grounded in everyday farming practice.
Newcastle University are involved with the project’s mitigation development as well as working within the Cumbria and South-West Scotland Farm Network. The team is working closely with SRUC experts Professor John Newbold and Dr Holly Nisbet, alongside AHDB Farm Liaison Officer Jess Graham, to provide specialist academic expertise that supports the effective implementation of mitigation strategies.
During visits to participating farms, researchers discuss the mitigation options farmers are considering and begin linking those decisions to management changes and measurable outcomes. A distinctive element of the project is the installation of low-cost methane sensors, known as ‘sniffers’, developed by Newcastle University, which will be installed on participating farms in the coming months.
While ‘sniffer’ is a convenient shorthand, the underlying technology is a metal-oxide gas sensor. What sets this approach apart is the integration of the low-cost sensors to monitor methane emissions seamlessly during milking, without disrupting cow behaviour or normal farm routines.
At the University’s farm, the system operates discreetly within a conventional herringbone milking parlour. As cows place their heads into the feed trough, a narrow tube positioned near the muzzle draws in air, which is directed over the sensor by a small pump. Using the existing parlour system, each reading is precisely matched to the correct cow at the exact moment she occupies the stall.
Video assessments confirm that cows remain completely undisturbed by the equipment, continuing their routine as normal. Meanwhile, the sensor records methane and carbon dioxide concentrations and securely uploads the data to cloud storage. This enables continuous measurements from every cow, twice daily, across the whole lactation.
The UK-DCN is using a range of methane measurement technologies and will be the first project to install this specific sniffer system on commercial farms. The first installation will focus on a farm using a robotic milking system, which has expressed interest in reducing methane emissions through changes to feed management. On another farm, emissions will be measured in parallel with a GreenFeed™ unit, providing a valuable comparison between the two systems.
The long-term potential of the resulting dataset is substantial. With continuous records spanning seasons, feeding changes and stages of lactation, researchers and farmers will be able to identify animals that naturally emit less methane, investigate when and why emissions rise or fall, and test when management adaptations are most effective at reducing emissions.
Looking ahead, success will be defined by the ability to quantify and verify the impact of management changes on methane emissions and the overall GHG footprint of each farm. Equally important is ensuring that the positive practices farmers adopt to reduce emissions are formally recognised. The overarching goal is to make methane data accessible, affordable and genuinely valuable for farmers.