Moroki Yuko, Tanaka Toshio
Graduate School of Veterinary Science, Azabu University, Sagamihara, Japan.
Anim Sci J. 2016 Aug;87(8):1055-62. doi: 10.1111/asj.12525. Epub 2015 Nov 19.
To improve the welfare of caged laying hens, a pecking device made of stones was introduced on the cage floor. Twenty-four White Leghorn hens aged 15 months were divided into four groups: single-housed hens with device, single-housed control hens, pair-housed hens with device and pair-housed control hens. Hens housed with the device pecked at various pecking objects less often than control hens. Agonistic behavior was also lower in hens with the device than in hens without the device, implied a possibility of improvement in quality of pecking stimuli with the device. Not only time spent pecking, but also quality of pecking might be important to fill their need for stimulation. Both single- and pair-housed hens more often pecked at the device in the evening. Response to various pecking objects also showed that pecking behaviors were most frequently expressed in the evening. Increased foraging at dusk is a well-known habit; therefore, the increase in pecking behavior in the evening might reflect the hens' general circadian rhythm. These results indicate that the device made of stones could promote some instinctive behavior. Enhancement of behavioral repertories and reduced agonistic behavior with the pecking device might improve the welfare of caged laying hens.
为了提高笼养蛋鸡的福利，在笼底引入了一种由石头制成的啄食装置。将24只15月龄的白来航蛋鸡分为四组：配备装置的单笼饲养母鸡、单笼饲养对照母鸡、配备装置的双笼饲养母鸡和双笼饲养对照母鸡。配备该装置饲养的母鸡啄各种啄食对象的频率低于对照母鸡。配备装置的母鸡的攻击性行为也低于未配备装置的母鸡，这意味着该装置有可能改善啄食刺激的质量。不仅啄食所花费的时间，而且啄食的质量对于满足它们对刺激的需求可能都很重要。单笼和双笼饲养的母鸡在晚上都更频繁地啄该装置。对各种啄食对象的反应也表明，啄食行为最常在晚上表现出来。黄昏时觅食增加是一种众所周知的习性；因此，晚上啄食行为的增加可能反映了母鸡的一般昼夜节律。这些结果表明，由石头制成的装置可以促进一些本能行为。使用啄食装置增加行为模式并减少攻击性行为可能会改善笼养蛋鸡的福利。
