Ninomiya Shigeru, Nishi Ayumi, Nakamura Ririka, Shibata Mitsuhiro
Faculty of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan.
Graduate School of Natural Science and Technology, Gifu University, Gifu 501-1193, Japan.
Animals (Basel). 2024 Dec 24;15(1):13. doi: 10.3390/ani15010013.
In intensive beef production systems, social dominance relationships among cattle and human-cattle relationships constantly affect cattle welfare. However, these factors have not been investigated to assess their long-term effects on cattle welfare. In this study, the relations of hair cortisol concentrations of group-housed pregnant cows with their social rank and avoidance distance when approached by humans were analysed. Thirty-two Japanese black cows were used in this study. Examinations were conducted six times throughout two years, and each cow was subjected to one-three examinations. Hair sampling was conducted on each examination day. The hair cortisol concentrations were measured using a cortisol enzyme immunoassay kit. Social behaviour recordings were made about 6 h on each examination day. The numbers of occurrences of butt, threat, chase, and avoidance behaviours of each animal were recorded using continuous recording methods, and the social rank score for each animal was calculated from the data. Avoidance distances from humans approaching were measured for 23 test cows during the first three examination days. Measurements were taken 5-10 min after the start of morning feeding. The relations between the hair cortisol concentration and social rank score or avoidance distance were analysed using a mixed-effects model or correlation analysis. Significant positive correlation was found between the social rank score and hair cortisol concentration (F = 4.54, = 0.038). No significant correlation was found between the cows' responsiveness to humans and their hair cortisol concentration (r = -0.004, = 0.99, = 23). The findings suggest that low-ranking cows had lower cortisol levels.
在集约化肉牛生产系统中，牛群之间的社会等级关系以及人与牛的关系不断影响着牛的福利。然而，尚未对这些因素进行调查以评估它们对牛福利的长期影响。在本研究中，分析了群体饲养的怀孕母牛的毛发皮质醇浓度与其社会等级以及被人类接近时的回避距离之间的关系。本研究使用了32头日本黑牛。在两年内进行了六次检查，每头牛接受一至三次检查。在每次检查日进行毛发采样。使用皮质醇酶免疫分析试剂盒测量毛发皮质醇浓度。在每次检查日进行约6小时的社会行为记录。使用连续记录方法记录每只动物的顶撞、威胁、追逐和回避行为的发生次数，并根据这些数据计算每只动物的社会等级得分。在最初的三个检查日，对23头试验牛测量了它们对接近的人类的回避距离。在早晨喂食开始5 - 10分钟后进行测量。使用混合效应模型或相关分析来分析毛发皮质醇浓度与社会等级得分或回避距离之间的关系。发现社会等级得分与毛发皮质醇浓度之间存在显著正相关（F = 4.54，P = 0.038）。未发现奶牛对人类的反应性与其毛发皮质醇浓度之间存在显著相关性（r = -0.004，P = 0.99，n = 23）。研究结果表明，低等级母牛的皮质醇水平较低。
