An automatic method for scoring poultry footpad dermatitis with deep learning and thermal imaging

Abstract

Footpad dermatitis (FPD) is a common poultry condition that can negatively influence chickens’ production, welfare, and health. However, no automated tool for monitoring FPD in live chickens is currently available. The objective of this study was to develop and optimize deep learning models to monitor hens’ FPD scores (i.e., 0–2 scale with higher scores indicating poorer footpad conditions). A total of 700 Hy-Line W-36 hens were raised in four cage-free housing systems integrated with Electrostatic Particle Ionization and various bedding materials. A GoPro camera with an upward lens was placed inside a transparent box. Individual laying hens were placed on the top surface of the box to acquire RGB images. In addition, a thermal camera was used to record RGB and thermal images of footpads, and the images were manually scored to assess their footpad conditions. Preprocessing techniques (e.g., filtration, separation, and augmentation) were deployed to enhance dataset quality and size. Moreover, YOLOv8 models (YOLOv8n, YOLOv8s, YOLOv8m, YOLOv8l, and YOLOv8x) and YOLOv7 models (YOLOv7 and YOLOv7x) were comparatively evaluated for predicting FPD scores. The results show that the YOLOv8l outperformed other models, with higher recall (96.6 %), mAP@0.50 (97.0 %), and F1-score (95.0 %). Additionally, the YOLOv8l-FPD model exhibited a high mAP@0.50 for score 0 (98.0 %), score 1 (95.0 %), and score 2 (97.9 %) and F1-score (95.0 %) for all FPD scores. Notably, using thermal images could result in faster convergence of model training and slightly better FPD score prediction performance than RGB images. The proposed technique can be useful for non-invasive automatic FPD scoring and further improve automation levels and animal welfare in the egg industry.