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Research note: The effect of passionflower supplementation on feather pecking in laying hens
Elizabeth Brass1, Jack O'Sullivan1, Helen Gray1
1School of Natural and Environmental Sciences, Newcastle University, UK, NE1 7RU.
Abstract:
Feather pecking is a significant issue in non-caged poultry welfare that results in the removal or damage of the feather of a hen. The most common forms are classified into gentle feather pecking and severe feather pecking which, if undeterred, can develop into cannibalism. This case study explored one aspect of the prevention of feather pecking, investigating if the feed additive Gallicalm, containing Passionflower, reduced feather pecking behavior in a free-range flock. Video footage over 6 weeks was analysed for feather pecking incidence in 2-week phases; Pre-Treatment, Treatment and Post-Treatment. Standard commercial rations were fed in the Pre-Treatment and Post-Treatment phases, with the Treatment phase receiving the standard commercial ration plus 1 kg per ton of Gallicalm. Feather scores were completed using the AssureWel method at the end of each phase, with production data collected through an online flock management tool. A total of 373 minutes of footage from 18 days was analysed for pecking behavior. Supplementation resulted in reduced number of severe feather pecks in the Pre-Treatment phase to the Treatment phase. Gentle pecking failed to decrease significantly during Gallicalm Treatment but increased in the post-Treatment phase. Aggressive, stereotypical and beak pecking were rare in all experimental phases. Feather scores deteriorated between the Pre-Treatment and Treatment phase but plateaued between the Treatment and Post-Treatment phase. This case study provides the first evidence of passionflower-containing supplements reducing feather pecking in laying hens. Given the billions of laying hens kept globally and the extensive welfare and economic issues associated with feather pecking, we advocate for further study to build on our initial findings.
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