School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK.
The Lakes Free Range Egg Company, Penrith, UK.
Vet Rec. 2021 Jun;188(12):e245. doi: 10.1002/vetr.245. Epub 2021 Apr 19.
Piling, a behaviour where hens crowd together, is referred to as smothering if mortalities result. Smothering is a considerable concern for the egg industry, yet is vastly understudied.
During an outbreak of recurrent smothering, continuous video footage captured a commercial, free-range flock over 35 days. We describe the piling behaviour observed and potential associations with productivity and flock health indicators.
Forty-eight piles were filmed, with a maximum density of 187.93 birds/m and up to 1204 birds in one pile. Piling occurred in the same house location on 33 of 34 observation days, the first evidence of regularity in piling behaviour. Despite extreme bird densities, we did not find associations between piling extremity and productivity but did find associations with water:feed ratio and temperature range.
This study describes the most extreme level of piling reported in literature and offers new insights into this problem behaviour and its consequences.
如果鸡群因拥挤而死亡，这种行为被称为压死。压死是蛋鸡产业的一个重大问题，但研究甚少。
在反复发生的压死疫情中，连续的视频录像在 35 天内拍摄了一个商业自由放养鸡群。我们描述了观察到的堆积行为，并探讨了其与生产力和鸡群健康指标的潜在关联。
共拍摄到 48 个堆，最大密度为 187.93 只/平方米，最高可达 1204 只。在 34 天的观察中，33 天都在同一鸡舍位置发生堆积，这是首次证明了堆积行为具有规律性。尽管鸟类密度极高，但我们没有发现堆积极端程度与生产力之间的关联，但发现了与水料比和温度范围的关联。
本研究描述了文献中报道的最极端的堆积水平，并为这种行为问题及其后果提供了新的见解。
