Minimally-invasive welfare assessment in pigs: A practical approach along the production chain

Animal welfare risks can arise and accumulate throughout the pig production chain, from the farm to transport, lairage, and slaughter. This presentation examines how minimally invasive indicators can support routine, evidence-based welfare assessment while limiting disturbance to animals. Such indicators include farm records, behavioural observations, visual scoring, environmental sensors, microphones, thermal imaging, camera-based systems, wearable devices, and slaughterhouse feedback. Their selection should be based on validity, feasibility, repeatability, minimal disturbance, and the ability to guide practical action. On-farm minimally invasive indicators can be measured using Precision Livestock Farming (PLF) tools to monitor feeding and drinking behaviour, microphones to record pig vocalizations, thermal cameras to detect signs of disease, and computer vision systems to identify specific behaviours. During transport and lairage, indicators such as panting, slipping, falling, skin lesions, wounds, and infrared body-temperature measurements can help identify welfare risks related to handling, environmental conditions, and journey conditions. At slaughter, data on mortality, downer pigs, carcass lesions, tail damage, and carcass condemnations can provide valuable feedback on problems originating at any step of the production chain. These indicators can help develop a context-specific toolbox (based on well-known and readily applicable measures) that enables effective decision-making while limiting the burden of data collection. A practical case study will conclude the presentation.