Grant: Alliance Grants

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.