Department of Animal Science, Aarhus University, 8830 Tjele, Denmark.
Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Copenhagen, Denmark.
Poult Sci. 2020 Jan;99(1):21-29. doi: 10.3382/ps/pez510. Epub 2019 Dec 30.
Increasing environmental complexity, e.g., by providing environmental enrichment, has been suggested as a way to increase activity levels and improve leg health in broilers. The aim of this study was to investigate the effects of different types of environmental complexity on leg health and measures of welfare of fast-growing broilers housed according to conventional European legislation. A total of 58 pens with approximately 500 broilers each (Ross 308), corresponding to a stocking density of 40 kg/m, were used. A total of 8 treatment groups, of which 5 were enrichment treatments (roughage, vertical panels, straw bales, and elevated platforms at 5 and 30 cm) and 3 were standard resources manipulations [increased distances between feed and water (7 m and 3.5 m), stocking density reduced to 34 kg/m, and 1 control group (1.5 m distance between feed and water and no enrichment objects)] were randomly assigned to each pen. At 35 D of age, 60 birds from each pen were assessed for gait, footpad dermatitis, hock burns, plumage cleanliness, presence of scratches, and leg deformities. Birds housed with 30 cm elevated platforms had worse gait compared to those housed with straw bales and at the lower stocking density of 34 kg/m (P = 0.004 and P = 0.001). Broilers from the control group also had worse gait compared to those housed at 34 kg/m stocking density. In addition, birds housed with access to a 30 cm elevated platform had healthier footpads compared to birds housed with access to straw bales (P = 0.0001) and with increased distance between feed and water (P = 0.011). Furthermore, birds housed with straw bales had worse footpad condition compared to birds with access to a 5 cm elevated platform (P = 0.002). There were no observed treatment effects on scratches, plumage cleanliness, leg deformities and body weight (P > 0.05). Based on the welfare indicators used in the present study, decreased stocking density has the potential of improving animal welfare, whereas the effects of elevated platforms need to be further studied before a final conclusion can be drawn, as footpad health was positively affected, but walking ability was impaired.
增加环境复杂性，例如提供环境丰容，可以提高肉鸡的活动水平并改善腿部健康。本研究旨在调查不同类型的环境复杂性对腿部健康和福利措施的影响，这些措施是根据欧洲传统法规饲养的快速生长的肉鸡。总共使用了 58 个鸡笼，每个鸡笼约有 500 只肉鸡（罗斯 308），相当于 40 公斤/米的饲养密度。共有 8 个处理组，其中 5 个是丰容处理组（粗饲料、垂直板、草捆和 5 厘米和 30 厘米高的平台），3 个是标准资源处理组[增加饲料和水之间的距离（7 米和 3.5 米），饲养密度降低到 34 公斤/米，和 1 个对照组（饲料和水之间的距离为 1.5 米，没有丰容物）]，随机分配到每个鸡笼中。在 35 日龄时，从每个鸡笼中抽取 60 只鸡评估步态、脚垫皮炎、跗关节烧伤、羽毛清洁度、划痕和腿部畸形。与饲养在草捆中的鸡相比，饲养在 30 厘米高平台上的鸡步态更差，与饲养在 34 公斤/米的较低饲养密度相比（P=0.004 和 P=0.001）。对照组的鸡的步态也比饲养在 34 公斤/米的饲养密度的鸡差。此外，与饲养在草捆中的鸡相比，饲养在 30 厘米高平台上的鸡的脚垫更健康（P=0.0001），与增加饲料和水之间的距离相比（P=0.011）。此外，与饲养在 5 厘米高平台上的鸡相比，饲养在草捆中的鸡的脚垫状况更差（P=0.002）。在划痕、羽毛清洁度、腿部畸形和体重方面没有观察到处理效应（P＞0.05）。根据本研究中使用的福利指标，降低饲养密度有可能改善动物福利，而高架平台的影响需要进一步研究，因为脚垫健康得到了改善，但行走能力受到了损害。
