Occurrence and reasons for On-Farm Emergency Slaughter of cattle in Northern Italy: human intelligence and machine learning (artificial intelligence) approaches

The management and culling of cattle at the end of their productive life raise significant concerns regarding animal welfare. When an animal is injured, farmers face three possible options: to treat the animal, hoping for its recovery; to humanely euthanize it; or to proceed with an on-farm emergency slaughter (OFES), with the approval of an Official Veterinarian. Regulation (EC) No. 853/2004 defines OFES as the emergency slaughter of domestic ungulates outside of a slaughterhouse, due to an “accident” that prevents their transport. In April 2022, the Italian Ministry of Health (Circular No. 13895 of April 5, 2022) provided an update regarding the interpretation of the term “accident”. This study investigated the OFES cases sent to slaughterhouses of the Local Competent Authority (LCA) of Brescia from 2021 to 2023, focusing on occurrence and reasons for OFES, on cattle characteristics, and the findings collected during the post-mortem inspection. Data were extracted from the electronic dataset of the LCA, with the reasons provided in free text format by the Official Veterinarians, categorized through both manual analysis and artificial intelligence (AI) techniques, including the Term Frequency – Inverse Document Frequency (TF-IDF) method and supervised machine learning. The analysis revealed a decrease in the OFES cases delivered to the slaughterhouses in Brescia, together with a change in the type of reason. Locomotion problems, such as fractures and acute injuries, accounted for 69.4% of OFES cases, increasing from 58.1% in 2021 to 78.9% in 2023. In contrast, cases of paresis or paralysis decreased from 19.4% to 8.2%, while those related to calving-related problems fell from 13.6% to 9.0%. AI tools demonstrated an ability to categorize OFES reasons with an agreement of 99.2% compared to manual interpretations. The analysis of post-mortem inspections revealed that 93.4% of OFES carcasses were suitable for human consumption, although the percentage of condemned carcasses increased from 5.2% in 2021 to 9.1% in 2023. Additionally, the portions of the carcass most frequently excluded from human consumption were the limbs and joints, representing 39.3% of exclusions, with an increase from 37.6% in 2021 to 44.9% in 2023. The study highlighted the shift in the motivations for OFES that occurred in Northern Italian farms and sent to the slaughterhouses in Brescia, following updates provided by the Ministry of Health. This underscored the complexity of the issue and the need for further research to explore the management, economic, or other factors that may influence the occurrence and reasons for OFES. Furthermore, the potential use of advanced analysis through artificial intelligence could facilitate and enhance the interpretation of these data, contributing to improving interventions for the welfare of cattle.