Aggressive and severe feather pecking in brown and white feathered leghorn pullets - Will blue light during brooding and rearing improve future egg production?

进攻性啄羽和自相残杀是影响食用鸡蛋行业动物福利和生产经济的重要问题。已经利用了许多缓解技术，包括饲料形式、能量水平、喙处理、饲养系统、光照强度等。尽管这些做法可能会降低发病率/严重性，但不能阻止行为的发生。随着生产者转向地面饲养小鸡，为更广泛的蛋鸡饲养系统做准备，这一点更加令人担忧。最近，我们的研究团队完成了一项研究，比较了由LED灯泡提供的光色处理(蓝色、绿色或白色)饲养的肉鸡。光的强度是通过用“Clux”(校正后的勒克斯，或鸡的勒克斯)测量仪测量的，这种测量仪是基于鸟类的视觉能力而不是人类的视觉能力来测量强度的。在生产或健康参数方面，浅色的影响微乎其微，但蓝光显著改变了行为和鸟类的影响(恐惧和压力)。在蓝光下饲养的肉鸡比在绿光或白光下饲养的肉鸡压力更小，也更害怕。更舒适的行为被注意到，鸟类看起来更平静。出现这种情况的部分原因可能是，肉鸡在蓝光下的视觉能力比在白光下的视觉能力有所提高，这与古老的行业说法不同，即使用蓝光可以减少攻击性，因为鸟类看不到东西。一般来说，轻质成分被认为对鸟类有类似的影响，尽管火鸡和肉鸡之间略有不同。如果情况确实如此，那么我们特别感兴趣的是，如果利用光色，特别是蓝光，是否可以减少发生在小鸡群中的攻击性啄食损害。已有研究表明，浅色对蛋鸡的繁殖有积极作用。据作者所知，目前尚不清楚孵化和饲养阶段的蓝光是否会对产蛋量或产蛋量产生负面影响，因为这一领域缺乏研究。

Aggressive feather pecking and cannibalism are significant issues affecting animal welfare and production economics in the table egg industry. Numerous mitigation techniques have been utilized, including feed form, energy levels, beak treatment, housing systems, light intensity, etc. Although these practices may reduce the incidence/severity, none stop the behaviour from occurring. This is even more concerning as producers move towards floor rearing pullets, in preparation for more extensive housing systems for laying hens. Recently, our research team completed a study comparing broilers reared on light colour treatments (blue, green, or white light) provided by LED bulbs. Light intensity was equalized by measuring with a "clux" (corrected lux, or chicken lux) meter, which measures intensity based on bird, rather than human, visual capacity. Minimal benefit of light colour was noted for production or health parameters, but blue light dramatically changed behaviour and bird affect (fear and stress). Broilers reared under blue light were less stressed and fearful than those reared under green or white light. More comfort behaviours were noted, and birds appeared calmer. Part of the reason this may have occurred is that the broilers had improved visual ability under blue light than under white light, which differs from the old industry verbiage that the use of blue light reduces aggression because birds do not see as well. In general, light components are thought to have similar effects on birds, although slight differences are noted between turkeys and broilers. If this is indeed the case, then we are particularly interested in understanding if utilizing light color, specifically blue light, could reduce the aggressive pecking damage that occurs in pullet flocks. It has been shown that light colour can have a positive effect on reproduction in laying hens. To the authors' knowledge, it is unknown if blue light during the brooding and rearing phase would negatively affect onset of egg production or egg production level as research is lacking in this area.