Department of Animal Sciences, University of Florida, Gainesville 32611.
Antelliq Innovation Center, Netanya, Israel 4250553; Center for Animal Welfare, Department of Animal Science, University of California, Davis 95616.
J Dairy Sci. 2020 Sep;103(9):8360-8368. doi: 10.3168/jds.2020-18419. Epub 2020 Jul 16.
With growing interest in provision of brushes for cattle and the implications of brush use for behavioral development and welfare, there is a need to validate methodology for quantifying grooming behavior. Our objectives were to characterize patterns of brush use, including bouts, diurnal activity, and individual variability over 24-h periods, and to validate time-sampling methodologies to characterize these traits, including instantaneous recording at various time intervals and continuous recording for subsets of the day. Data sets from previous experiments involving steers (experiment 1; n = 18) and heifers (experiment 2; n = 64), consisting of start and end times of brush use continuously recorded from video, were used to analyze brush use. We extrapolated data sets representative of a range of instantaneous recording intervals and compared daily brush duration and bout characteristics with corresponding values from continuous recording using linear regression. To assess validity of sampling subsets of the day, we selected 2-h time periods representative of different functional parts of the day and compared hourly brush rates with continuous data using Spearman's rank order correlation (r). Brush use was variable among individuals. All steers used the brush in experiment 1, but 17% (n = 11 of 64) of heifers in experiment 2 did not. Bout analysis revealed that individuals used the brush for an average of 7 to 8 brush bouts lasting 4 to 6 min, leading to an average of 24 and 36 min/d for experiments 1 and 2, respectively. Cattle used the brush mainly during daylight hours, with peaks around sunrise, sunset, and the afternoon. Instantaneous recording at intervals less than 1 to 3 min, depending on the experiment, provided good estimates of daily brush use duration (R > 0.95 and slope and intercept not different from 1 and 0, respectively), but intervals >3 min were less reliable. For bout characteristics, the intercept of the modeled line differed from 0 for most recording intervals for both experiments, and the slope differed from 1 for recording intervals >30 s in experiment 1, suggesting that time sampling may have underestimated true values. Of the 2-h periods compared with 24 h of observation, 1800 to 2000 h was most highly correlated (r = 0.84) for experiment 1, and 1800 to 2000 h and 1400 to 1600 h were the most highly correlated (r = 0.71 and 0.74, respectively) for experiment 2 with daily values. When using time-sampling methods to characterize brush use, we suggest that the recording interval used and time of day observed should be carefully considered, as time sampling at an interval of 1 to 3 min may measure daily brush use duration, but continuous recording may be required to capture bout characteristics.
随着人们对为牛提供刷子的兴趣日益浓厚，以及刷子使用对行为发展和福利的影响，因此有必要验证定量梳理行为的方法。我们的目标是描述刷子使用模式，包括使用刷子的时间段、昼夜活动和 24 小时内的个体差异，并验证时间采样方法来描述这些特征，包括在不同时间间隔进行即时记录和在一天的部分时间进行连续记录。以前涉及牛（实验 1；n = 18）和小母牛（实验 2；n = 64）的实验中使用的数据集，这些数据集由视频连续记录的刷子使用的开始和结束时间组成，用于分析刷子使用情况。我们推断了一系列具有代表性的即时记录间隔数据集，并使用线性回归比较了每日刷子使用持续时间和使用时间段特征与连续记录的对应值。为了评估一天中抽样子集的有效性，我们选择了代表一天不同功能部分的 2 小时时间段，并使用 Spearman 等级相关系数（r）比较了每小时的刷子使用频率与连续数据。个体之间的刷子使用情况存在差异。所有牛在实验 1 中都使用了刷子，但在实验 2 中，有 17%（n = 64 中的 11 头）的小母牛没有使用刷子。使用刷子的分析显示，个体平均使用刷子进行 7 到 8 次使用，每次持续 4 到 6 分钟，分别导致实验 1 和实验 2 中每天 24 到 36 分钟。牛主要在白天使用刷子，在日出、日落和下午有高峰。根据实验的不同，间隔小于 1 到 3 分钟的即时记录可以很好地估计每日刷子使用时间（R > 0.95，斜率和截距与 1 和 0 没有差异），但间隔大于 3 分钟的记录则不太可靠。对于使用时间段特征，两个实验的大多数记录间隔的模型线的截距都与 0 不同，并且在实验 1 中，记录间隔大于 30 秒的斜率与 1 不同，这表明时间抽样可能低估了真实值。在与 24 小时观察相比的 2 小时时间段中，实验 1 中 1800 到 2000 小时的相关性最高（r = 0.84），而实验 2 中 1800 到 2000 小时和 1400 到 1600 小时的相关性最高（r = 0.71 和 0.74），与每日值相同。当使用时间采样方法来描述刷子使用情况时，我们建议应仔细考虑使用的记录间隔和观察时间，因为 1 到 3 分钟的间隔进行记录可能可以测量每日刷子使用时间，但可能需要连续记录才能捕捉使用时间段特征。
