Stracke Jenny, Andersson Robby, Volkmann Nina, Spindler Birgit, Schulte-Landwehr Jan, Günther Ronald, Kemper Nicole
Institute of Animal Science, Ethology, University of Bonn, Bonn, Germany.
Institute for Animal Hygiene, Animal Welfare and Farm Animal Behavior, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
Front Vet Sci. 2022 May 17;9:888503. doi: 10.3389/fvets.2022.888503. eCollection 2022.
Footpad dermatitis (FPD) is an indicator of animal welfare in turkeys, giving evidence of the animals' physical integrity and providing information on husbandry management. Automated systems for assessing FPD at slaughter can present a useful tool for objective data collection. However, using automated systems requires that they reliably assess the incidence. In this study, the feet of turkeys were scored for FPD by both an automated camera system and a human observer, using a five-scale score. The observer reliability between both was calculated (Krippendorff's alpha). The results were not acceptable, with an agreement coefficient of 0.44 in the initial situation. Therefore, pictures of 3,000 feet scored by the automated system were evaluated systematically to detect deficiencies. The reference area (metatarsal footpad) was not detected correctly in 55.0% of the feet, and false detections of the alteration on the footpad (FPD) were found in 32.9% of the feet. In 41.3% of the feet, the foot was not presented straight to the camera. According to these results, the algorithm of the automated system was modified, aiming to improve color detection and the distinction of the metatarsal footpad from the background. Pictures of the feet, now scored by the modified algorithm, were evaluated again. Observer reliability could be improved (Krippendorff's alpha = 0.61). However, detection of the metatarsal footpad (50.9% incorrect detections) and alterations (27.0% incorrect detections) remained a problem. We found that the performance of the camera system was affected by the angle at which the foot was presented to the camera (skew/straight; < 0.05). Furthermore, the laterality of the foot (left/right) was found to have a significant effect ( < 0.001). We propose that the latter depends on the slaughter process. This study also highlights a high variability in observer reliability of human observers. Depending on the respective target parameter, the reliability coefficient (Krippendorff's alpha) ranged from 0.21 to 0.82. This stresses the importance of finding an objective alternative. Therefore, it was concluded that the automated detection system could be appropriate to reliably assess FPD at the slaughterhouse. However, there is still room to improve the existing method, especially when using FPD as a welfare indicator.
脚垫皮炎（FPD）是火鸡动物福利的一个指标，能证明动物的身体完整性，并提供有关饲养管理的信息。屠宰时用于评估FPD的自动化系统可以成为客观数据收集的有用工具。然而，使用自动化系统要求它们能够可靠地评估发病率。在本研究中，通过自动化摄像系统和人类观察者使用五分量表对火鸡的足部进行FPD评分。计算两者之间的观察者可靠性（克里彭多夫α系数）。结果并不理想，初始情况下的一致性系数为0.44。因此，对自动化系统评分的3000只足部图片进行了系统评估，以发现缺陷。在55.0%的足部中，参考区域（跖部脚垫）未被正确检测到，在32.9%的足部中发现了对脚垫改变（FPD）的误检测。在41.3%的足部中，足部没有正对着摄像头。根据这些结果，对自动化系统的算法进行了修改，旨在改善颜色检测以及跖部脚垫与背景的区分。现在用修改后的算法对足部图片重新进行评估。观察者可靠性得到了提高（克里彭多夫α系数=0.61）。然而，跖部脚垫的检测（50.9%的误检测）和改变的检测（27.0%的误检测）仍然是个问题。我们发现摄像系统的性能受足部对着摄像头的角度（歪斜/笔直；P<0.05）影响。此外，发现足部的左右侧性有显著影响（P<0.001）。我们认为后者取决于屠宰过程。本研究还突出了人类观察者观察者可靠性的高度变异性。根据各自的目标参数，可靠性系数（克里彭多夫α系数）范围为0.21至0.82。这强调了找到客观替代方法的重要性。因此，得出的结论是，自动化检测系统可能适合在屠宰场可靠地评估FPD。然而，现有方法仍有改进空间，尤其是在将FPD用作福利指标时。
