Record milk output may mask future cow shortage, AHDB warns

Britain’s record milk production could be masking a looming shortage of future dairy cows, AHDB has warned.

The levy board believes more dairy farmers are using beef genetics, raising concerns that too few dairy heifers are being bred to safeguard future milk output.

GB milk production reached record levels last year, but AHDB attributed this to higher yields per cow rather than growth in the national dairy herd. The GB dairy cow herd has continued its long-term decline, falling by 2% in the latest dataset.

Latest British Cattle Movement Service data recorded a 0.4% year-on-year increase in 2025 births to dairy dams in Great Britain, although AHDB noted that the rise was largely driven by dairy-beef calves rather than future dairy replacements.

These are calves born to dairy cows but sired by beef bulls, making them more suitable for the beef market than future milk production.

In 2025, 60% of registrations to dairy dams had a beef sire, while 32% were dairy heifer calves. Annual registrations of dairy females to a dairy sire have been falling since 2021.

The 2025 total stood at 463,373 head, down 3.1% year-on-year and the lowest figure on record.

AHDB has questioned whether enough of these animals will reach first lactation to support future production.

The warning comes as the age profile of the dairy herd points to further pressure ahead.

AHDB linked a previous rise in youngstock numbers in the early 2020s partly to mistrust in sexed semen and subsequent “over-serving”. That group is now moving through the milking herd, with many cows reaching their fourth lactation, when herd exits typically increase.

As of April 2026, BCMS data showed the 4-6 year old category of dairy females was the only age group recording year-on-year growth.

As older cows leave the herd and fewer dairy heifers come through, AHDB expects the national milking herd to tighten in the years ahead.

Cow longevity may help ease some of the pressure. As of April 2026, the average age of a cow in the GB milking herd stood at 4.6 years, slightly older than the previous year.

Previously attractive milk prices may have encouraged some producers to retain cows for longer, although a recent rise in dairy cull throughputs suggests some farmers have also been “clearing out” their herds.

Dairy cull throughputs were up 17% year-on-year in March, although the increase slowed to 3% in April.

There are also anecdotal reports of some farmers keeping cows for another lactation to produce another calf for the beef market.

AHDB highlighted some benefits to this approach, including more lactations, lower heifer replacement costs and better carbon footprints. But it warned this must be balanced against slower genetic progress and the risk of problems if disease or other herd issues arise.

Strong beef prices have made beef calves a more attractive option for many dairy businesses, while weaker milk prices have reduced the incentive to breed extra dairy replacements.

Improved beef genetics, integrated schemes and growing consumer awareness of popular cross-breeds, such as Angus, have also supported the trend.

Beef supplies were short and prices remained strong through much of last year, although they have fallen back in 2026. Finished cattle prices have weakened in recent months due to reduced demand, but calf values have remained in annual growth, which could continue to encourage the use of beef semen.

The shift is not only market-led, according to AHDB, but also structural, with more dairy business models now set up specifically to rear beef calves.

At the same time, AHDB pointed to positive signs in the dairy sector’s focus on efficiency, including a significant increase in genotypes submitted by dairy farmers for its genotype evaluation service.

While this does not necessarily mean more heifers are being produced, the levy board suggested it showed greater interest in the long-term success of dairy herds.

Genetic testing and sexed semen are allowing producers to make more targeted breeding decisions by selecting the best-performing females. This reduces the need to overproduce replacement animals and can support higher yields, both in milk volume and solids, per cow.

AHDB argues that improved efficiency also helps reduce the environmental footprint of dairy farming.

However, it cautioned that breeding only the required number of replacement heifers, while putting the rest to dairy-beef, carries risks.

There could be too few dairy replacements available, especially for flying herds that depend on buying in animals. Disease risks from the continent could also limit supplies.

AHDB sees signs of future tightness in dairy heifer supply, linked to weaker confidence among dairy farmers and a focus on short-term beef revenues.

It linked this not only to milk price pressure, but also to wider agricultural challenges, including the end of BPS and uncertainty over funding for SFI schemes in England.

Despite these pressures, AHDB expects the longer-term outlook for dairy to be supported by rising global demand, with farmgate milk prices projected to improve later this year and into next.

As a result, dairy heifers are likely to become increasingly needed and more expensive.

The issue is not limited to Britain. In the US, strong beef prices and demand from new cheese plants have helped push replacement dairy cow prices to record highs.

In the EU, environmental regulations and incentives are reducing herd size, meaning the cows that remain must become more efficient and productive.

Producers may have to slow culling if markets start to incentivise greater milk production, given the time needed to breed more replacements.

Some farms may also look to flying herd systems to increase numbers more quickly. But without enough replacement heifers coming through, AHDB warned that dairy expansion could be constrained just as global demand and milk prices begin to improve.