Battery cages for egg-laying hens were banned in 2012, for instance. 例如，2012年禁止对蛋鸡使用多层鸡笼。

Legislative reforms have been harder to come by in America, especially at the federal level. 在美国，尤其是在联邦一级，立法改革已经变得更加困难。

Animal-welfare advocates lament the country’s congressional system, which gives disproportionate clout to rural states. 动物福利倡导者哀叹美国的国会制度给了农村各州不成比例的权力。

Nevertheless, a rare but significant state-level change came last November when Californians voted to pass Proposition 12, 然而，去年11月加州通过了第12号提案，这是一个罕见但意义重大的州级改革。

which will ban the production and sale of pork, veal and eggs from animals kept in cages, bringing the state’s laws roughly in line with those in the EU. 该法案将禁止从圈养动物生产和销售猪肉、小牛肉和鸡蛋，使得该州法律与欧盟法律大致一致。

The change affects all meat producers who want to sell in America’s biggest state, putting pressure on them to change their farming practices. 这一变化影响到所有想在美国最大州销售的肉类生产商，迫使他们改变养殖方式。

Public companies have been more responsive than lawmakers to animal-welfare concerns. 与立法者相比，上市公司对动物福利问题的反应更为积极。

Activists have achieved remarkable success in recent years by threatening companies with the release of unflattering images and videos of how their food is produced. 近年来，维权人士通过发布食品生产过程中的不雅图片和视频威胁企业，取得了显著的成功。

Research by the Open Philanthropy Project, a group which funds animal-welfare activists, finds that such campaigns have prompted more than 200 American companies—including Mc- Donald’s, Burger King and Walmart—to stop buying eggs from chicken raised in battery cages since 2015. 为动物福利活动人士提供资金的组织“开放慈善项目”的研究发现，自2015年以来，此类活动已促使包括麦当劳、汉堡王和沃尔玛在内的200多家美国公司停止购买电池笼饲养鸡产的鸡蛋。

Farmers are therefore increasingly interested in improving the lives of their birds. 由此农民对提高家禽的生活条件愈加上心。

Richard Swartzentruber owns two chicken sheds in Greenwood, a small town in Delaware. 理查德·斯瓦兹特鲁伯在特拉华州的小镇格林伍德拥有两个鸡舍。

The company he supplies, Perdue Farms, has stopped using antibiotics altogether. 他供应的公司珀杜农场已经完全停止使用抗生素。

Mr Swartzentruber’s chicken sheds have plenty of windows and doors that open onto a fenced grassy field whenever the weather permits. 斯瓦兹特鲁伯先生的鸡舍有很多对着用篱笆围起来的草地的窗户和门，只要天气允许，就会开窗开门。

This comes with trade-offs: chickens might like perching on trees, but so do hawks. 这是有代价的:鸡可能喜欢栖息在树上，但鹰也喜欢。

Inside the sheds, bales of hay, wooden boxes and plastic platforms are scattered around to entertain his chickens. 鸡舍里，一捆捆的干草、木箱和塑料平台散落在周围，用来喂鸡。

Such measures have helped him gain a good-farming certificate from the Global Animal Partnership, a charity. 这些措施助他获得了慈善机构全球动物伙伴组织颁发的优良农业证书。

Bruce Stewart-Brown, a food-safety scientist at Perdue Farms, says that his company would love to raise more organic chickens. 珀杜农场的食品安全科学家布鲁斯·斯图尔特·布朗说，他的公司很乐意饲养更多的有机鸡。

His ability to provide higherwelfare organic meat is ultimately constrained by market forces, since the feed legally required is pricey. 他提供更高福利的有机肉类的能力最终受到市场力量的限制，因为法律规定的饲料价格昂贵。

Although larger numbers of people might be willing to pay more for organic or free-range products, most still prefer whatever is cheapest. 尽管可能愿意为有机产品或散养产品支付更多钱的人越来越多，但大多数人仍然更喜欢最便宜的产品。

And, despite growing interest in vegetarianism and veganism, surveys find little evidence that many people in the rich world are turning into herbivores. 尽管人们对素食主义和纯素食主义的兴趣日益浓厚，但调查发现，几乎没有证据表明很多发达国家的人正在变成食草动物。

People may like flirting with plant-based diets. 人们可能喜欢偶尔吃植物饮食换换口味。

But what they really love is chicken. 但们真正喜欢的还是鸡肉。