The truth about dead chickens

China consumes 4.7 billion chickens a year, most of them raised in battery farms. But what are the health consequences for birds and humans? Jiang Gaoming and Tang Aimin investigate the shady underbelly of China’s poultry industry.
<p>A battery farm in Shangdong, China (Image: Alamy)</p>

A battery farm in Shangdong, China (Image: Alamy)

Battery farming was introduced to the villages of northern China 23 years ago, replacing free-range chicken rearing. All of a sudden, broiler chickens could be brought to maturity in 50 days (rather than the usual 200) and egg layers could produce nearly 300 eggs a year. One breed was a real “egg-laying machine” and it became known as the “288” – after the number of eggs it could lay in a year! These imported techniques were welcomed with open arms by farmers and scientists alike. Studying zoology at university, I even went on a class trip to see battery farming in action.

Now battery farming is the norm in China, but its problems are becoming ever more apparent. It ignores the birds’ real needs, and crams seven or eight of them into each square metre. Additives, antibiotics and drugs are used in great quantities to increase production and profits – not to mention hormones that are harmful to human health. And the farmers themselves will admit these problems, saying: “We’re not going to eat the chickens – we just sell them to the cities.”

Many chickens die in the battery farms, despite farmers’ efforts to prevent this. A large farm will house 20,000 to 30,000 birds, and every year an average of at least 1,000 will die. But what happens to all these carcasses? To find out, we conducted a survey in a number of northern Chinese provinces, and the results were chilling: 80% of the dead birds end up in the human food chain.

So how does this happen? One route is factories producing processed meat “sausages.” The dead birds are very cheap – 0.4 to 0.6 yuan (US$0.05 to US$0.07) a kilogram – and the bosses of small-scale factories are often happy to buy them. Villagers told us that you will find people waiting around the factories looking to buy carcasses, or farmers will sometimes have direct links to factory bosses. Sick birds are likely to be sold off at the same time. Just pluck them, gut them, cook them and mix in some starch and preservatives – all that is needed for one of these sausages.

Stall-holders selling roast chicken also see the profits to be made from dead or sick birds, since they are much cheaper than healthy ones. They choose chickens that are close to death and get them onto the spit as soon as possible. Think about that next time you are tempted by a street-side chicken leg in China. An avian disease specialist once told me he bought a roast chicken before boarding a train, and was shocked to discover millimetre-thick, yellowish-white protein deposits in its heart and liver, indicating the chicken had died of an infection. The stall-holder obviously had not had time to clean the bird properly before cooking and selling it. The expert may have been able to tell the difference, but who else could? It was the last chicken he ate.

Carcasses also end up indirectly entering the food chain when they are used to feed other animals. This happens in one of two ways: they are either sold to farmers raising foxes or marten for their fur; or, more dangerously, they are used to feed pigs. There is an east China avian hospital that dissects 25 to 50 kilograms of chicken every day to diagnose avian diseases. In the past they employed someone to take the carcasses out of the city and bury them, but now animal farmers buy them for pig feed at 0.8 yuan (US$0.10) a kilogram. As a consequence, the dead and dissected birds enter the food chain. This operation earns the hospital enough money that they will turn a blind eye to the meat’s destination.

Although more ethical farmers see the dangers of selling the carcasses and deal with disposal themselves, this can still be a problem. Proper disposal would cost money, so the farmers will cut corners. One farmer, who lived close to a city, would dump dead birds into a disused well. The well filled up over several years, and now the stench carries for miles in the summer. And while the odour may not be dangerous in itself, the toxins and bacteria working their way into the water table are.

Ideally, the carcasses should be incinerated on the farm, but this is a less popular option since it is more costly. When there is a outbreak of bird flu, an alarmed government will offer 10 yuan per chicken as compensation for farmers who incinerate them, but the money will not always arrive. Local government is often reluctant to admit there is a problem in their area. And even when they do, bureaucratic “red tape” stands between farmers and their compensation. Farmers will need to apply to the local animal health station, get authorisation at a provincial level, and the list goes on. Farmers know this and will often take the easier option – and allow the birds to enter the food chain. After all, they will not even eat the healthy chickens, let alone the dead ones.

There are other routes for the carcasses to end up in our stomachs, from restaurants, dumpling stalls and more. There is no need to list them one by one, but the problem is a major one. Food additives, steroids, colourants, toxic pesticides, fast-acting fertilisers and genetically-modified foods are available on the market, and it is easy to believe they are being misused. Businesses seek profits; farmers want to increase their earnings; and certain government departments neglect their duties. All threaten the health of consumers: we suffer the consequences of these unnatural farming methods.

So what can we do, when China consumes 4.7 billion chickens a year? Chickens must be free of their cages and given space to roam on China’s grasslands, hills and forests – and live their natural lives – only then should China’s people feel safe to eat chicken.


Jiang Gaoming is a Professor at the Chinese Academy of Sciences’ Institute of Botany and a doctoral candidate tutor, Vice Secretary-General of UNESCO’s China-MAB Committee and member of the UNESCO MAB Urban Group. He is recognized for his introduction of the concepts of “urban vegetation” and “using natural forces to restore China’s ecosystems.”

Tang Aimin is chair of the China Scientific View of Development Research and Development Centre. His work on how Guizhou will develop in the knowledge economy was well-received by leaders in Guizhou and Guiyang.