Humane Society International, Farm Animals, 2100 L St. NW, Washington, DC 20037, USA.
Humane Society of the United States, Farm Animals, 2100 L St. NW, Washington, DC 20037, USA.
Animals (Basel). 2013 May 13;3(2):386-400. doi: 10.3390/ani3020386.
In most areas of the world, broiler chickens are raised in floor systems, but cage confinement is becoming more common. The welfare of broiler chickens in cages is affected by movement restriction, poor bone strength due to lack of exercise, and prevention of key behavioral patterns such as dustbathing and ground scratching. Cages for broiler chickens also have a long history of causing skin and leg conditions that could further compromise welfare, but a lack of controlled studies makes it difficult to draw conclusions about newer cage designs. Cage environments are usually stocked at a higher density than open floor systems, and the limited studies available suggest that caging may lead to increased levels of fear and stress in the birds. Further, birds reared on the floor appear less likely to harbor and shed Salmonella, as litter may serve as a seeding agent for competitive exclusion by other microorganisms. Cages for laying hens used in egg production have met with substantial opposition due to welfare concerns and caging broiler chickens will likely be subject to the same kinds of social disapproval.
在世界上大多数地区，肉鸡都是在地板系统中饲养的，但笼养越来越普遍。笼养肉鸡的福利受到运动限制、缺乏运动导致的骨骼脆弱以及无法进行尘土浴和地面刨食等关键行为模式的影响。肉鸡笼具的使用历史很长，会导致皮肤和腿部问题，进一步损害其福利，但由于缺乏对照研究，很难对新型笼具设计得出结论。笼舍环境的饲养密度通常高于开放式地板系统，而且现有有限的研究表明，笼养可能会导致鸟类产生更多的恐惧和压力。此外，在地板上饲养的禽类不太可能携带和传播沙门氏菌，因为垫料可能成为其他微生物竞争排斥的启动因子。由于对福利的担忧，用于蛋鸡生产的蛋鸡笼具遭到了强烈反对，而笼养肉鸡可能也会受到同样的社会反对。
