Researchers aimed to investigate the relationship between commercially applied environmental enrichment (EE), plumage condition, and fearfulness. Forty-five indoor multi-tiered aviary system flocks of laying hens from across Norway were visited at end of lay (70-76 wk of age). Data was collected on five types of enrichment: pecking stones, gravel, oyster shells, scattered grains, and “toys”. Feather loss was assessed individually in 50 hens per flock using the NorWel method. Assessment was done visually, to avoid disturbing the flock, and scores were awarded using a 3-point scale. Fearfulness was measured using a novel object (NO) test which measured the number of hens that approach the NO in a set period of time. The NO test was performed in four different locations in each hen house.
The results of the study showed that there was no correlation found between the number of hens approaching the NO and the age at which each type of EE was provided. Providing toys at an early age was correlated with a reduction in the amount of tail damage at the end of the production period. Increasing the amount of gravel stones also showed a positive effect on the condition of the tail feathers.
While it could not be proven that gravel stones directly affected feather peaking incidence, results suggest that the grit provision most likely functions as a diversion for hens to focus foraging and pecking activity. Therefore, it seems that enrichment objects that increase the quality and complexity of litter can help minimize peaking behavior.
Producer Takeaway: In aviary systems, the impact of enrichment objects increases if provided early in life and in larger quantities.