When you think about animal cruelty, you might think of chained-up dogs left to suffer in the cold, stray cats struggling to survive on the streets, or depressed polar bears at the zoo. As terrible as many cats, dogs, and zoo animals have it, the animals that are both the most numerous and that have it worst — by far — are farmed animals.
The world’s biggest animal cruelty problem, explained in one chart
It’s the most invisible — and the hardest to solve.
Getty Images/iStockphoto
Kenny Torrella is a senior reporter for Vox’s Future Perfect section, with a focus on animal welfare and the future of meat.
But the biggest problem they face isn’t necessarily the cruel, overcrowded, unsanitary factory farm, where the vast majority of animals raised for meat, milk, and eggs are confined. Nor is it the inhumanity of the slaughterhouse. Rather, the most severe animal welfare problem in today’s meat industry is largely invisible to the naked eye. I’m talking about their genes.
The most stark example is the chicken, which accounts for around 95 percent of animals raised for food in the US, at 9.4 billion birds. Globally, over 75 billion chickens are slaughtered every year.
Over the last 80 years, the poultry industry has significantly altered chickens’ genetics, breeding them to grow as big as possible in as little time as possible, all in an effort to quickly and efficiently pump out more and more chicken. In 1960, it took nine weeks, or 63 days, in the US for a chicken to reach slaughter weight at a tiny 3.35 pounds.
By 2024, according to the US trade group National Chicken Council, chickens reached slaughter weight in under seven weeks, or 47 days. And they’re nearly twice as heavy as chickens were 65 years ago, weighing in at 6.57 pounds.
This rapid growth takes an enormous toll on the chickens’ bodies, with many in pain due to lameness, or difficulty walking. As I wrote last year:
Among other traits, poultry companies selectively bred chickens to have bigger breasts, the most valuable part of the bird. As a result, today’s chickens are extremely top-heavy compared to chickens of the past.
Animal advocates say this transformation has turned the birds into “Frankenchickens” that are “prisoners in their own bodies,” which cause a number of health problems that lead to premature death. Many chickens’ tiny legs can’t support the weight of their giant breasts, leading to injuries that can be so severe that they struggle to walk to reach food and water, resulting in death by dehydration or starvation.
Last year, 6 percent of US chickens raised for meat — more than half a billion individuals — died on the farm and never even made it into the food supply. That’s due to issues including disease spread and complications from their rapid growth, like heart failure and “sudden death syndrome,” a somewhat mysterious disease in which young, fast-growing chickens — seemingly out of nowhere — flip over and die or briefly, intensely flap their wings and die.
I recently covered an investigation into America’s fourth largest chicken company, called Mountaire Farms, which highlights some of these problems. Investigators found some birds too weak to reach food, and a number of dead and decaying birds among living chickens.
While chickens account for the vast majority of animals raised for food, all of the main farmed species have been genetically altered to varying degrees in the US:
- Dairy cows today have been bred to produce almost 8 gallons of milk daily, more than five times that of dairy cows in the 1940s; this intensive output is associated with increased metabolic stress, mastitis, and premature death, among other issues.
- Like chickens, pigs have been bred to grow bigger, which can cause mobility problems.
- Since the 1990s, female breeding pigs — most of whom are confined in tiny crates for their entire lives — have been selectively bred to produce almost 40 percent more piglets per litter, which can affect both their health and that of their piglets.
- Between 1977 and 2007, beef cattle became 30 percent heavier at slaughter, and reached their slaughter weight 20 percent faster.
- Turkeys in the early 2000s grew twice as fast, and twice as big, compared to turkeys from the 1960s.
- In the late 1940s, hens laid 137 eggs annually, which has since more than doubled to 290 eggs per year. Egg-laying hens’ incredibly high output has led to bone fragility and high rates of fractures.
This constant tinkering with the genetics and reproductive systems of farmed animals has enabled the livestock industry to squeeze more food out of each animal and make meat, milk, and eggs cheaper, thereby increasing consumption of these foods — a vicious cycle that has led to animal suffering on an unfathomable scale.
The problem has also been largely invisible to consumers, which has made it difficult for animal advocates to make progress. Many food companies have pledged to buy meat from slower-growing chickens in the US, but few have followed through, though there has been some progress in Europe.
Banning the most apparent cruel livestock industry practices — like tiny cages, searing off hens’ beaks, or cutting out male piglets’ testicles without anesthesia — may be obvious and sensible things to do in the eyes of most consumers. But “better genetics” isn’t as intuitive and doesn’t quite have the same ring as “ban cages” or “stop mutilating animals.” It’s also a more fundamental challenge to factory farms’ business model.
Yet breeding and genetics are just as, if not more, important than anything else policymakers and meat companies could do to reduce the suffering of billions of animals on America’s factory farms.
