Shoji Gaku, Tochinai Ryota, Sekizawa Shin-Ichi, Kuwahara Masayoshi
The University of Tokyo Graduate School of Agricultural and Life Sciences Faculty of Agriculture, Japan.
The University of Tokyo Graduate School of Agricultural and Life Sciences Faculty of Agriculture, Japan.
Poult Sci. 2025 May 17;104(8):105256. doi: 10.1016/j.psj.2025.105256.
In egg production management, housing systems have been one of the major issues. Although most laying hens are housed in conventional cage (CC) worldwide, alternative systems have been adopted such as enriched cage (EC) and aviary systems (AV) mainly due to concern of animal welfare of hens. To properly evaluate housing systems from production performance and welfare status, we investigated egg production, and physiological and autonomic nervous functions of hens by using a telemetry system and HRV analysis. Hens in AV showed lower productivity compared to CC and EC, and shell characteristics were quite similar between housing systems. The results also presented that egg laying rate (ELR) of EC was higher than that of CC. As physiological parameters, we continuously recorded an electrocardiogram (ECG), heart rate (HR), body temperature (BT) and locomotor activity (LA) of hens in three different housing systems by a telemetry system. Also, to evaluate autonomic nervous function of hens as a way to investigate stress and welfare of hens on poultry farms, we analyzed heart rate variability (HRV). Hens in all three groups showed the diurnal HR and LA patterns. CC and EC had also diurnal patterns of autonomic nervous functions, suggesting that parasympathetic nervous activity is predominant during dark phase. On the other hand, these diurnal patterns were unclear in hens raised in AV, which implies that AV may suppress parasympathetic nervous activity of hens during the dark phase. Therefore, AV might diminish the rest quality of hens, and lower the biological functions and recover of hens. In addition to that, hens in AV did not increase LA by quantitative analysis. It can be concluded that AV could be harmful to egg production and welfare of hen, and that EC system seems to be a more reasonable alternative option for conventional egg production from both egg productivity and animal welfare point of views.
在蛋鸡生产管理中，饲养系统一直是主要问题之一。尽管全球大多数蛋鸡饲养在传统鸡笼（CC）中，但由于对母鸡动物福利的关注，已采用了替代系统，如富集鸡笼（EC）和放养系统（AV）。为了从生产性能和福利状况方面正确评估饲养系统，我们使用遥测系统和心率变异性（HRV）分析研究了母鸡的产蛋量、生理和自主神经功能。与CC和EC相比，AV中的母鸡生产力较低，不同饲养系统之间的蛋壳特性相当相似。结果还表明，EC的产蛋率（ELR）高于CC。作为生理参数，我们通过遥测系统连续记录了三种不同饲养系统中母鸡的心电图（ECG）、心率（HR）、体温（BT）和运动活动（LA）。此外，为了评估母鸡的自主神经功能，以此来研究家禽养殖场中母鸡的应激和福利情况，我们分析了心率变异性（HRV）。三组母鸡均呈现出昼夜心率和运动活动模式。CC和EC也有自主神经功能的昼夜模式，表明在黑暗阶段副交感神经活动占主导。另一方面，在AV中饲养的母鸡，这些昼夜模式不明显，这意味着AV可能会在黑暗阶段抑制母鸡的副交感神经活动。因此，AV可能会降低母鸡的休息质量，并降低母鸡的生物学功能和恢复能力。除此之外，通过定量分析，AV中的母鸡运动活动没有增加。可以得出结论，AV可能对母鸡的产蛋和福利有害，从产蛋生产力和动物福利的角度来看，EC系统似乎是传统蛋鸡生产中更合理的替代选择。
