The effects of environmental enrichment on broiler chicken behaviour (#562)
The provision of enrichment items is intended to increase the welfare of animals in captivity, and is often mandatory for welfare assurance schemes. However the effect of such items is poorly understood and evidence of successful, practical enrichment items is often lacking. We investigated the effects of enrichment, either physical items or increased human contact, on the behaviour of broiler chickens. Day-old mixed-sex ROSS 308 broilers (n=108) were allocated to a control (C), physical environmental enrichment (P) or human contact (H) group. Birds were housed in nine groups of 12 in 1m2 pens, visually isolated from other pens. Physical items included a perch, rope, chains, balls, shredded paper and woodblock. The H birds were exposed twice daily to a human walking through the pen for five minutes with intermittent stationary periods. Behaviour and interactions with enrichment items (P birds) was monitored hourly three times a week, for three weeks between 7.00-23.00 h by instantaneous point sampling. Data were analysed by GLM or non-parametric Kruskal-Wallis tests. The P birds performed less ground pecking and foraging than C and H birds (P, mean 6.8% of observation points (±0.55); C, 10.3 (±0.73); H, 9.4 (±0.68); P<0.001), however appeared to compensate by interacting with enrichment items (P, mean 3.0 (± 0.36)). P birds interacted most with the woodblock and shredded paper (69.1% and 13.8%, respectively; P≤0.05), but items most commonly provided in industry were rarely used (6.6%, 6.2%, 3.3%; rope, chains and perch, respectively). There were no treatment effects on resting or comfort (i.e. preening, dust bathing) behaviours. Our results suggest that provision of this enrichment has no effect on resting and comfort behaviours, and interacting with physical items appears to substitute ground pecking and foraging. Furthermore, enrichment items typically utilised by industry are not preferred by broilers, and thus their effectiveness is questionable.