1Department of Animal Science,Aarhus University,Blichers Allé 20,8830 Tjele,Denmark.
2Department of Agroecology,Aarhus University,Blichers Allé 20,8830 Tjele,Denmark.
Animal. 2019 May;13(5):1037-1044. doi: 10.1017/S1751731118002689. Epub 2018 Oct 16.
Tail damage within the production of finisher pigs is an animal welfare problem. Recent research suggests that removal of known risk factors may not be enough to eliminate tail biting, especially in undocked pigs, thus a different strategy is worth investigating. This could be early detection of tail biting, using behavioural changes observed before tail damage. If these early stages of tail biting can be detected before tail damage occurs, then tail damage could be prevented by early interventions. The first step in developing such a strategy is to identify the types of behaviour changes that emerge during early stages of tail biting. Thus, the aim of the current study was to investigate whether pen level activity and object manipulation evolved differently during the last 7 days before the scoring of tail damage (day 0) for pens scored with tail damage (tail damage pens) and pens not scored with tail damage (matched control pens). The study included video recordings for twenty-four tail damage pens and thirty-two matched control pens. Activity level and object manipulation were observed the last 7 days before day 0 during the morning (0600 to 0800 h), afternoon (1600 to 1800 h) and evening (2200 to 2400 h, only activity level). Both activity level and object manipulation were analysed using generalised linear mixed effects models with a binomial distribution for activity level and a negative binomial distribution for object manipulation. The probability of being active was higher in tail damage pens compared to control pens during the afternoon the last 5 days before day 0 (P<0.001). This was seen due to a decrease in activity level in the control pens, which makes it difficult to identify future tail damage pens from this difference. Object manipulation was lower in tail damage pens compared to the control pens on all 7 days before day 0, but only in pens with undocked pigs (P<0.01). Thus, it is still unknown when this difference in object manipulation initiated. It was concluded that both activity level and object manipulation seemed related to ongoing tail biting and should be investigated through more detailed observations and for a longer time to establish the normal behaviour pattern for a particular pen. Thus, it is suggested that future research focusses on developing automatic monitoring methods for pen level activity and object manipulation and applies algorithms that establish and detect deviations from the normal behaviour pattern of the pen before tail damage.
猪在育肥阶段尾部受损是一个动物福利问题。最近的研究表明，即使消除了已知的风险因素，也可能不足以杜绝咬尾行为，尤其是在未去尾的猪中，因此值得研究其他策略。这种策略可以是在尾巴受损之前通过观察行为变化，尽早发现咬尾行为。如果在尾巴受损之前能够发现咬尾的早期阶段，就可以通过早期干预来防止尾巴受损。开发这种策略的第一步是确定在咬尾的早期阶段出现的行为变化类型。因此，本研究的目的是调查在出现尾巴损伤评分（第 0 天）的前 7 天（尾巴损伤前 7 天）内，尾巴损伤评分的猪圈（尾巴损伤猪圈）和未评分的猪圈（配对的控制猪圈）的猪圈水平活动和物体操纵是否会有不同的发展。该研究包括 24 个尾巴损伤猪圈和 32 个配对控制猪圈的视频记录。在第 0 天之前的最后 7 天内，在早上（0600 至 0800 小时）、下午（1600 至 1800 小时）和晚上（2200 至 2400 小时，仅活动水平）观察活动水平和物体操纵。使用具有二项分布的广义线性混合效应模型分析活动水平和具有负二项分布的物体操纵，以分析活动水平和物体操纵。在第 0 天之前的最后 5 天的下午，尾巴损伤猪圈的活跃概率高于控制猪圈（P<0.001）。这是由于控制猪圈的活动水平下降，使得很难从这种差异中识别出未来的尾巴损伤猪圈。在第 0 天之前的所有 7 天，尾巴损伤猪圈的物体操纵均低于控制猪圈，但仅在未去尾的猪圈中差异显著（P<0.01）。因此，物体操纵差异开始的时间尚不清楚。结论是，活动水平和物体操纵似乎都与正在进行的咬尾行为有关，应该通过更详细的观察和更长的时间来进行研究，以建立特定猪圈的正常行为模式。因此，建议未来的研究集中于开发猪圈水平活动和物体操纵的自动监测方法，并应用建立和检测猪圈尾巴受损前正常行为模式偏离的算法。
