Where you’re born can determine your lot in life. It’s true for humans, but surprisingly it’s the same for cattle. Specifically: which country a cow is born into determines whether that cow gets to live outdoors, or whether they’re kept in concrete sheds for their entire life.

In the UK, cows chomping contentedly on rolling green hills is a quintessential sight. But not everyone does things this way. In the US, most cattle spend only their first few months of life grazing on grass, before being confined to a crowded dirt pen (a “feedlot”) until the day they go to slaughter. Most US dairy cows never get to go outside. In Denmark, 70% of dairy cows are now permanently confined indoors, up from just 16% in 2001. This practice is often called “zero-grazing”.

Denmark is a warning of how quickly animal welfare can be undermined if the public is not watching. Shockingly, the same is happening in the UK, right under our noses. Investigations by the Guardian (see also) and the BBC in the last few years have revealed that the UK cattle industry is silently converting to zero-grazing operations. They fly under the radar due to a loophole; unlike pig and poultry farms, large cattle farms do not have to register with DEFRA or obtain environmental permits. This means we do not even know exactly how prevalent it is, with estimates from 5% to as high as 20%. But the investigations are showing that whatever the baseline, it is rising.

One of the key reasons given for expanding zero-grazing in the UK is food security. The corporations, factory farmers and other groups argue that it increases the resilience of the UK food system, reduces prices for consumers and is better for farmers. However, the facts show that more zero-grazing cows undermine UK food security in a number of ways.

Zero-grazing proponents argue that it allows us to produce more beef and dairy for UK consumers. This is true. But more beef and dairy would not make the UK more food self-sufficient. In fact, the UK produces enough beef and dairy to largely satisfy domestic demand, and has done for the last 2 decades. We only import specialist products that cannot be made at home, such as specialist European cheeses like feta and parmesan. Crucially, UK consumers are moving away from beef, and demand for dairy may have stalled. Producing more food that British people do not want does nothing for food security.

Another key pillar of UK security is the affordability of a nutritious diet for all. Whilst beef and dairy can be sources of important nutrients, we can easily get these nutrients from other sources, typically much cheaper than beef.

Furthermore, many food security experts argue that a food system that promotes obesity lowers food security. All reputable medical bodies (including the NHS) agree that the UK public consumes more red meat than is healthy, and red meat contributes to many health problems, costing the NHS millions in treatment costs.

While proponents argue that zero-grazing systems reduce food costs, they are likely to increase costs to taxpayers (pollution, subsidies, agricultural jobs). The apparent reduction in food costs is more than offset by the added tax costs to fix these issues.

Indoor animal agricultural systems like zero-grazing dramatically increase the risk of catastrophic disease outbreaks. Cramming thousands of animals into confined spaces, with poor ventilation and chronic stress, suppresses their immune function. This creates ideal conditions for pathogens to emerge, mutate, and spread. We have already witnessed what this looks like in other intensively farmed species: African swine fever has devastated pig populations across Asia and Europe, triggering global supply crises. Closer to home, wave after wave of bird flu has forced the culling of millions of birds in the UK alone. 

Cattle are not immune to this process. By concentrating UK cattle into large indoor units, we would be setting the stage for bird-flu level disease to emerge. Such an outbreak could wipe out a significant portion of the national herd overnight, devastating our milk supply and ruining farmers’ livelihoods. This is the opposite of food security.

If zero-grazing is so clearly bad for food security, why is it growing? The fact is that UK cattle farmers struggle to earn enough from their work. On lowland grazing farms, many cattle farmers struggle to even turn a profit most years. This is because big meat corporations/processors and supermarkets squeeze farmers tighter and tighter in order to minimise costs to consumers and maximise profit to themselves. Many are also intensifying because they are increasingly having to compete with low-welfare, cheaper imports from other countries.

The UK must tackle its food security problems, and many UK cattle farmers truly are in crisis, but zero-grazing is not the answer to either. If we look at pig farming, where intensive indoor farming is far more established, we can see that it does not bring more security for farmers. Pig farmers still struggle to remain consistently profitable, demonstrating that intensification alone cannot overcome the structural power imbalances in the meat industry. Any increases in farmer profits that come from being able to produce meat more cheaply are immediately eroded by the large meat corporations and supermarkets.

What’s worse, zero-grazing could leave some farmers worse off. If consumer demand stays constant or continues to decline, any increased sales from one cattle farmer must come at the cost of sales to another cattle farmer. Some will benefit, but only because others go bust. As has always been the case, the larger factory farmers will outcompete the small traditional farmers. Overall, British cattle farmers would be no better off. In fact, the remaining farmers could also be worse off, because if the beef and dairy supply exceeds demand, it drives down prices and farmer incomes. 

We can see this in the data on farming jobs. The Conservative Animal Welfare Foundation’s Hidden Harms of Factory Farms report estimated that the industrialisation of the pig and poultry sectors between 2000 and 2019 is thought to have resulted in 14,000 jobs not created across the agricultural sector. Industrial animal agriculture automates at every opportunity, employing far fewer people than the traditional farms they replace. The headline figures for the sector may look stable, but behind them is a steady hollowing-out of rural employment; some farmers gain, whilst many more are driven out of the industry entirely.

This situation might be avoided if farmers export excess beef and dairy (though milk is hard to export due to spoilage), but is it really a solution to UK food security for some farmers to stop producing food for the British public? Competing with other beef exporting countries on international markets has no guarantee of being profitable and brings its own risks and challenges.

We believe there are 2 better solutions for the real problems facing British cattle farmers:

Some cattle farmers will balk at the idea of moving away from cattle; they may feel they are abandoning the calling of their fathers and grandfathers before them. However, will zero-grazing really be any better? Though the farmer can still claim the job title of cattle farmer, their day to day will be unrecognisable. Instead of presiding over fields of green, their time will be spent among rows and rows of restless, bloated cows who will never get to express their natural behaviours. On the other hand, land conversion could allow cattle farmers to remain true to a key duty of every UK farmer: to be stewards of the Great British countryside.

We modelled the additional grain required from a shift from 5% of the UK dairy herd kept in zero-grazing to 100%. Our method is as follows:

• Estimate the feed concentrate required for pasture-raised cattle and zero-grazed cattle (detailed below). We estimate that a cow moved from a pasture-based system to a housed system would require an extra 1,724 kg of feed concentrate per year.
• Convert the concentrate requirements into grain requirements, as concentrate contains more than just grain (e.g. protein, by-products of other industries and minerals). DAERA recommends a grain percentage of between 30-45% for concentrates. As our choice of this number strongly affects the final results, we calculate outcomes under both.
• Apply the differences in concentrate requirements per cow to 95% of the dairy herd. The UK dairy cow population is 1.85 million (DEFRA, June 2025), so switching 95% involves providing additional grain to 1,757,500 cows. 
• As a result, the UK would require 3.03 Mt of additional concentrate per year translating into 0.91 to 1.36 Mt of cereals per year.
• Total domestic cereal demand (animal feed, human & industrial) was approximately 24.4 Mt at the time of DEFRA’s cattle census: animal feed alone is ~13.3 Mt.
• This means that total livestock feed cereal demand could increase by 6.8-10.2%.
• In the same time period the UK imported 6.4Mt of grains, 26% of demand. As a result it is reasonable to assume that any additional grain required for zero grazing would need to come from imports.
• This means that a transition to zero-grazing for UK dairy could increase grain imports by 14.2-21.2%.

We compared proxies for pasture-based and zero-grazing dairy systems. Good quality UK data segmented by system was not available, so we use Irish data as a reasonable proxy. For the pasture end, we used the Teagasc Irish national average (2017-2019), which draws on the Irish National Farm Survey and ICBF data and represents a spring-block, grass-dominant system averaging 5,484 kg of milk and 1,176 kg of concentrate per cow per year; Teagasc is the Irish state agency for agricultural research (source). For the zero-grazing end, we used housed herd data from a 31-farm Northern Ireland study (2018-2019) by AFBI, the Agri-Food and Biosciences Institute, which is Northern Ireland’s primary agricultural research body, where the fully housed Holstein-Friesians averaged 8,800 kg of milk and 2,900 kg of concentrate per cow per year (source).

We assume that our datasets are good proxies of UK pasture-raised and zero-grazed systems. In reality, the Teagasc Irish national average is likely to underestimate the amount of grain as Irish systems are known to use less concentrate than the rest of the UK. However, AFBI data is also likely an underestimate, as it is not a full “zero” grazing system. We assume that these two underestimates approximately cancel out.

• We do not model additional grain requirements from moving the beef cattle system to zero-grazing, only dairy cattle. 
• We model cereal grains only, defined as wheat, barley, maize, and oats.
• We do not model additional protein that zero-grazed cattle require, such as soyabean meal, rapeseed meal, field beans, much of which is imported.