New findings from the UK Dairy Carbon Network (UK-DCN) show that the carbon footprint of milk is shaped by many small, everyday management decisions rather than any single factor. The work also highlights feed efficiency as the strongest driver of lower emissions and shows why establishing a comprehensive baseline is an important first step.
Understanding emissions is central to the UK-DCN project. All farms involved in the Farm Networks have completed a baseline carbon footprint using a consistent, streamlined approach designed to accurately estimate greenhouse gas (GHG) emissions. This baseline helps to understand where emissions come from on different farms and, crucially, establishes a benchmark against which future improvements can be measured as mitigation measures are put in place.
One of the clearest findings is the wide range of carbon footprints between farms who operate broadly similar systems. A farm’s carbon footprint reflects the cumulative effect of many small decisions made day in, day out. This reinforces a simple but important message: there is no silver bullet. Meaningful progress comes from stacking improvements over time rather than relying on one change to deliver everything.
The main sources of emissions are consistent across all systems. Enteric methane from the cow is the largest contributor to the carbon footprint of milk, followed by feed production – particularly purchased concentrates. Manure management also makes a significant contribution, while fertiliser manufacture and use, energy and livestock purchases account for smaller but still important shares. Although grazing, mixed and housed systems differ in how emissions are split, overall footprint values overlap considerably, underlining that management has more influence than the system.
The baseline also challenges some common assumptions. Higher milk yields, larger herds or more time housed do not automatically lead to a higher carbon footprint per litre of milk. Well-run, efficient systems can perform strongly on emissions regardless of scale or production level. Efficiency, rather than size, is what really matters.
Feed efficiency assessments reflect forage quality, ration formulation, cow health, genetics and consistent day-to-day management working together. Producing more milk from each kilogram of feed dry matter reduces emissions calculations in two ways: methane emissions are spread over more litres of milk, and emissions embedded in producing and purchasing feed are reduced.
The mitigation choices farmers are already making closely mirror these findings. Many are focusing on longer-term breeding decisions to improve efficiency, robustness and lifetime performance, recognising that genetic progress delivers lasting benefits.
Others are prioritising feed formulation, increasing milk from forage and improving grazing management to get more from home-grown feed. Animal health and welfare measures also feature strongly, reflecting the link between healthy cows, stable performance and lower emissions. Improvements in nutrient management, and the use of targeted fertiliser technologies where appropriate, are helping some farms improve nitrogen efficiency and reduce losses.
Modelling shows that most individual mitigation measures are likely to deliver relatively modest reductions when used in isolation. However, when several are combined, the impact becomes far more meaningful. The biggest and most resilient gains will come from sustained improvements in efficiency, gradual breeding and management changes and practical adjustments that fit the realities of each farm, rather than one-off fixes.
Working alongside farmers in the UK-DCN are ADAS’s Dr Steve Anthony and AFBI’s Dr Taro Takahashi, whose role is to interpret the data being collected and turn it into something genuinely useful – not only for individual businesses, but for the wider dairy industry and the UK’s GHG Inventory.
“The UK-DCN gives us a fantastic opportunity to gain real insight from experts who can translate complex data into practical, meaningful metrics for farmers and industry alike,” says Teaghan Tayler, Head of GB Farm Networks.
“Being able to draw on that expertise to better understand on-farm emissions profiles, and to identify solutions that work in real farming systems while also strengthening industry-level reporting, is hugely valuable and an exciting step forward for everyone involved.”
This baseline now provides a vital reference point for the next phase of the UK-DCN project. As mitigation measures are implemented, farms will be able to measure real change against their starting position, helping to identify what works best in different systems while continuing to support productivity and profitability.