The Problem With “Sustainable” Animal Agriculture

The animal agriculture industry has found another way to sell the same injustice back to the public: climate-friendly animals.

Not fewer animals used. Not fewer bodies bred, confined, mutilated, milked, made pregnant, loaded into trucks and killed. Just animals redesigned to produce more output with a lower emissions figure attached.

It is efficiency. And efficiency has always been the industry’s favourite word for extraction.

A recent UK advisory report warned that breeding animals for lower emissions and higher productivity can intensify the physical consequences already forced on animals. Sustainability schemes often measure emissions per unit of output, not the life being forced to produce that output. A kilo of flesh. A litre of milk. A dozen eggs. The body disappears behind the spreadsheet. That is the trick.

If a cow produces more milk, the emissions per litre may look better. If a chicken grows faster, the emissions per kilo of flesh may look better. If a hen lays hundreds of eggs before she is discarded, the system can call itself efficient.

But efficient for whom?

Not for the chicken bred to reach slaughter weight in weeks, whose body grows faster than her legs and organs can cope with. Modern chickens raised for flesh have been selected for rapid growth and oversized breast muscle. Studies link faster growth with worse walking ability, leg disorders, contact dermatitis, cardiovascular disease, heat stress and higher mortality. Even their parents are caught in the system, with birds who have the genetics for rapid growth often kept hungry to stop them growing too quickly. This is what the industry calls progress.

Laying hens tell the same story. In the early twentieth century, the average hen in the United States laid around 86 eggs a year. By the 1960s, that had risen to around 215. Now genetics companies celebrate flocks producing more than 500 eggs per hen housed in around 100 weeks.

Imagine doing that to someone’s body and calling it sustainability.

Egg shells require calcium. That calcium does not appear by magic. Hens are forced to draw from their own bodies, leaving them vulnerable to brittle bones, fractures and collapse. The industry sees a production milestone. The hen lives inside the cost.

Pigs are no different. Breeding sows for larger litters is sold as productivity, but larger litters are associated with more piglet deaths, more low birth weights, more competition for milk, starvation risk and extra pressure on the mother. Again, the unit of concern is not the sow. Not the piglet. The unit of concern is output.

Cows raised for flesh are being pushed in the same direction. In the US, average cattle carcass weight rose from 615 pounds in 1975 to 890 pounds in 2024. The industry credits genetics, hormones, pharmaceuticals and high-energy diets. Alongside those heavier bodies come lameness, heat stress, liver abscesses, congestive heart failure and deaths in feedyards. One feedlot director put it bluntly: “We are not making their lungs and hearts bigger.”

Exactly.

The profitable parts get bigger. The animal has to survive the design. This is what happens when living beings are treated as assets. One study estimated the global market value of farmed animals at between 1.61 and 3.3 trillion US dollars. That figure is meant to show economic importance. It also shows the moral problem. Their lives are priced. Their bodies are investments. Their reproductive systems are production tools. Their deaths are part of the business model.

So when climate policy enters this system without challenging animal use itself, it does not free animals from exploitation. It optimises the exploitation.

That is why “better meat” collapses so quickly under scrutiny. Shift from beef to chicken and emissions per gram of protein can fall, but many more individuals are killed for the same amount of protein. Move towards slower-growing chickens and their lives may be less physically extreme, but emissions can rise. Grass-fed and organic systems may sound nicer to consumers, but they can require more land and create higher climate impacts per gram of protein than conventional systems. Conventional systems can look more climate-efficient precisely because they are more intensive.

So the public is offered a false choice. Do you want fewer emissions or fewer animals killed? Do you want lower land use or less confinement? Do you want lower methane or fewer broken bodies? Do you want climate targets or animals with lives worth anything beyond output?

The trap is pretending one version of animal exploitation can solve the problems created by animal exploitation.

It cannot.

Animal agriculture uses more than three-quarters of agricultural land, contributes substantially to greenhouse gas emissions, drives methane pollution, uses crops that could feed humans directly, and turns billions of sentient individuals into climate variables. The entire system is built on converting plants into animal products at a biological loss, then pretending the answer is a better conversion rate. We do not need climate-friendly animal farming. We need to stop treating animals as farming equipment.

The food system transformation literature is already pointing in the obvious direction: more legumes, whole grains, fruits, vegetables and nuts, and less reliance on animal-sourced foods in high- and middle-income regions. One major economic report estimates current food systems create around 15 trillion US dollars a year in hidden costs and that transforming them could deliver 5 to 10 trillion dollars a year in benefits.

That transformation cannot be built on redesigning animals into more efficient commodities.

The animal agriculture industry wants the future to look like the present, just with better branding, better genetics and better emissions accounting.

But a lower-emission cage is still a cage. A more efficient slaughterhouse is still a slaughterhouse. A hen laying 500 eggs is not a climate solution. A chicken bred to grow slightly less grotesquely is not justice. A cow whose methane is managed is still a cow being used.

The question is not how to make animal exploitation more sustainable. The question is why anyone still thinks exploitation deserves a future.