Sustainability in Dairy: Why the Concept Still Stands Strong

Andy Warne, Dairy Sector Council Member (Independent), AHDB

A More Credible Foundation for Sustainability

Sustainability in dairy has evolved from a broad idea into a more reliable and transparent concept. Measurement tools are now better aligned, and inconsistencies between carbon calculators is being addressed through standardisation and improved data handling. Supply chains have also become more transparent as major retailers take responsibility for Scope 3 emissions.

Financial Sustainability and the National Herd

Sustainability must support two outcomes: resilient farm profitability and progress toward net zero. The pursuit of profitability and lower carbon are complementary activities. Recent figures show Great Britain’s milking herd fell to 1.63 million cows, the lowest on record, yet October 2023 milk output reached 1.309 billion litres, a 6.8% increase on the previous year, more milk from less cows is delivered by genetic progress.

Profit Lifetime Index: A Proven Impact on Profit

The Profitable Lifetime Index (PLI) has delivered sustained gains for over 25 years. One-third of the index reflects production, while the remainder reflects traits central to animal health and welfare which in turn deliver business resilience. A ProMAR study of 250 herds demonstrated that each additional PLI point was associated with £2.09 more margin per cow per year, with top-quartile herds realising roughly £34,000 more annual margin.

Genomics: Faster, Earlier, More Accurate Progress

Genomics enables earlier and more accurate identification of high-merit females. Weekly genomic releases and single-step genomic evaluation planned for 2026 reflects AHDB’s investment in improving genomic services. This follows cross-breed evaluations launched in 2025. 78% of milk-recorded cows are in herds registered for AHDB’s online genetic and genomic reports.

Environmental Sustainability: The EnviroCow Index

Long-term breeding for PLI has already reduced emissions. European data show a 10% drop in greenhouse gas equivalents over a decade alongside a 30% rise in production. EnviroCow provides a targeted method for selecting for carbon efficiency, explaining 37% of variation in carbon footprint and 80% of methane variation in an ARLA study.

Methane Sniffers and International Collaboration

AHDB is installing methane sniffers on 15 herds through DEFRA funding to directly measure methane output. The UK dataset of 7,500 cows will be combined with international datasets from Canada, the Netherlands and Denmark, creating 21,000 methane-genomic records.

Permanent, Compounding Gains

Genetic progress is permanent and cumulative. AHDB estimates genetic improvement may contribute £0.7 billion to financial and environmental sustainability over the next five years, demonstrating genetics as a long-term tool supporting both profitability and net-zero ambition.

Take-Home Messages

• Sustainability is strengthening because measurement tools and supply-chain transparency are improving.
• Financial and environmental sustainability must work together; profitability underpins long-term progress.
• PLI has a proven link to farm profitability and long-term herd improvement.
• Genomics accelerates and improves selection decisions across the herd.
• EnviroCow offers a powerful route for selecting for lower carbon and methane intensity.
• Genetic progress is permanent and compounds over time, making it central to net-zero strategies.