Department of Animal Sciences, University of Florida, Gainesville 32611.
Department of Animal Sciences, University of Florida, Gainesville 32611.
J Dairy Sci. 2019 Apr;102(4):3421-3430. doi: 10.3168/jds.2018-15460. Epub 2019 Feb 7.
Group housing allows for dairy calves to perform social grooming behavior; however, the use of mechanical brushes may influence how calves groom themselves and others. Our objectives were, first, to characterize the bout characteristics of brush use, self-grooming, and allogrooming in calves and, second, to evaluate the effects of access to a rotating brush on grooming behavior. Holstein heifer and bull calves (n = 32) were group-housed (4 calves/group) at 2 wk of life (17 ± 3 d of age; mean ± standard deviation) and followed to wk 7 of life. Pens were assigned to receive either a rotating brush (BR; n = 4 pens) or no brush (CON; n = 4 pens). Behavior was recorded continuously for 12 h for 2 focal calves/pen on 2 d during wk 4, 6, and 7 of life. We performed a bout analysis by fitting a mixture of normal distributions to the log-transformed frequency distribution of the intervals between recorded periods of behavior. We calculated bout criteria for brush use (125.9 s), allogrooming (125.9 s), and self-grooming (a mixture of 3 normal distributions provided the best fit for these data, providing 2 bout criteria: a shorter (micro) bout criterion of 50.1 s and a longer (macro) criterion of 1,000 s). Brush use was consistent across weeks, and calves used the brush for 20.5 ± 6.1 min/12 h observation period, in 31.1 ± 1.7 bouts (mean ± SE). The frequency and duration of allogrooming bouts did not differ between treatments and across time. The BR calves tended to self-groom more than CON calves (16.3 vs. 14.3 min/12 h; BR vs. CON; SE = 0.68), and time spent self-grooming decreased across weeks. The frequency and duration of self-grooming micro bouts did not differ between treatments, but BR calves had shorter, more frequent self-grooming macro bouts (10.58 vs. 9.46 bouts; BR vs. CON; SE = 0.24). In summary, we determined that bout criteria could be fitted to grooming behaviors, which may be useful when characterizing these behaviors in future work, and that providing access to a rotating brush influenced self-grooming behavior in group-housed calves.
群体饲养允许奶牛犊进行社交梳理行为；然而，机械刷子的使用可能会影响犊牛自我梳理和相互梳理的方式。我们的目标是，首先，描述刷子使用、自我梳理和相互梳理的行为回合特征，其次，评估接触旋转刷子对梳理行为的影响。荷斯坦小母牛和公牛犊（n = 32）在 2 周龄（17 ± 3 天龄；平均值 ± 标准差）时被群体饲养（每组 4 头犊牛），并饲养至 7 周龄。将围栏分配为接受旋转刷子（BR；n = 4 个围栏）或不接受刷子（CON；n = 4 个围栏）。在 4 、6 和 7 周龄期间的 2 天内，对每组 2 头犊牛的 12 小时连续行为进行记录。我们通过将记录的行为间隔的对数分布拟合正态分布混合物来进行行为回合分析。我们为刷子使用（125.9 秒）、相互梳理（125.9 秒）和自我梳理（混合 3 个正态分布为这些数据提供了最佳拟合，提供了 2 个回合标准：更短的（微观）回合标准为 50.1 秒和更长的（宏观）标准为 1000 秒）制定了回合标准。刷子使用在整个星期内保持一致，犊牛在 12 小时观察期内使用刷子 20.5 ± 6.1 分钟，使用 31.1 ± 1.7 次。在处理和时间上，相互梳理回合的频率和持续时间没有差异。BR 犊牛比 CON 犊牛更倾向于自我梳理（16.3 与 14.3 分钟/12 小时；BR 与 CON；SE = 0.68），且自我梳理时间随着周数减少而减少。BR 犊牛的自我梳理微观回合的频率和持续时间与 CON 犊牛没有差异，但 BR 犊牛的自我梳理宏观回合更短、更频繁（10.58 与 9.46 次；BR 与 CON；SE = 0.24）。总之，我们确定了可以应用于梳理行为的回合标准，这在未来的工作中对描述这些行为可能有用，并且提供旋转刷子的接触会影响群体饲养犊牛的自我梳理行为。
