Department of Animal Science, Aarhus University, DK-8830 Tjele, Denmark.
National Veterinary Institute, Technical University of Denmark, Kemitorvet, DK-2800 Kgs. Lyngby, Denmark.
Animal. 2020 Jan;14(1):119-128. doi: 10.1017/S1751731119001551. Epub 2019 Jul 16.
Recent data suggest that organic broilers often score worse on footpad lesions than conventional broilers but also that the current scoring of organic broiler feet may be misleading. In order to characterise footpad lesions in organic broilers, this study assessed and compared footpad lesions in a sample of 2987 conventional and 3578 organic broiler feet obtained from a large Danish abattoir during summer and winter. The feet were scored according to two scoring systems: the modified Danish surveillance scoring system and a histopathology-based new scoring system specifically developed to target the ability to differentiate between broiler feet with hyperkeratosis and ulcers. For both systems, all broiler feet with visible lesions were cross-sectionally incised. Significant differences between the two production systems were found for both scoring systems (χ2 = 710; P < 0.001 and χ2 = 247; P < 0.001 for the new and the surveillance systems, respectively), showing that a larger proportion of the organic feet compared to conventional feet - summer and winter - exhibited signs of hyperkeratosis. In addition, a smaller fraction of the organic feet than of the conventional feet were given the outermost scores, that is, normal or ulcerated; 13.4% v. 25.3% broiler feet were given score 0 for organic v. conventional production systems, respectively (χ2 = 152; P < 0.001), and 18.4% v. 23.8% feet were given score 4 for organic v. conventional production systems, respectively (χ2 = 308; P < 0.001). Thus, the results suggest that surveillance scoring systems such as the one used in Denmark are useful for the examination of footpad lesions in broilers from both types of production systems. However, the results have also raised attention to a typical characteristic of the feet of organic broilers, that is, profound hyperkeratosis, which may underlie potential misclassifications in surveillance scoring systems like the one used in Denmark. Among the possible solutions to this challenge to the correctness and fairness of the scoring system are improved procedures (such as mandatory incision), training of technicians and calibration of results (especially for the organic footpads).
最近的数据表明，有机肉鸡的脚垫病变评分往往比传统肉鸡差，但目前对有机肉鸡脚垫的评分可能存在误导。为了描述有机肉鸡的脚垫病变，本研究评估并比较了从丹麦一家大型屠宰场夏季和冬季获得的 2987 只常规肉鸡和 3578 只有机肉鸡的脚垫病变。这些脚按照两种评分系统进行评分：改良丹麦监测评分系统和一种基于组织病理学的新评分系统，该系统专门用于区分有角质过度和溃疡的肉鸡脚。对于这两种系统，所有有可见病变的肉鸡脚都进行了横切。两种生产系统之间的两个评分系统都存在显著差异（χ2=710；P<0.001 和 χ2=247；P<0.001，新系统和监测系统），表明与传统肉鸡相比，有机肉鸡的脚垫有更多角质过度的迹象。此外，有机肉鸡的脚得到最外层评分（即正常或溃疡）的比例小于传统肉鸡的脚，有机肉鸡的脚分别有 13.4%和 18.4%得到 0 分，而传统肉鸡的脚分别有 25.3%和 23.8%得到 0 分（χ2=152；P<0.001），有机肉鸡的脚分别有 18.4%和 13.4%得到 4 分，而传统肉鸡的脚分别有 23.8%和 25.3%得到 4 分（χ2=308；P<0.001）。因此，结果表明，丹麦等国家使用的监测评分系统可用于检查两种生产系统的肉鸡脚垫病变。然而，结果也引起了人们对有机肉鸡脚部的一个典型特征的关注，即严重的角质过度，这可能导致丹麦等国家使用的监测评分系统出现潜在的错误分类。针对评分系统的正确性和公正性面临的这一挑战，可能的解决方案包括改进程序（如强制横切）、技术员培训和结果校准（特别是有机脚垫）。
