Evaluating the synergistic impact of season and transport distance on bovine mortality during transport to slaughter

Transport-related mortality is a key indicator of animal welfare. This study evaluated the effects of season, transport distance, and their interaction on mortality in cows, heifers, fattening cattle, and calves transported to slaughter. The analysis was based on data collected in cooperation with the State Veterinary Administration on bovine transports to slaughterhouses in the Czech Republic from 2017 to 2023. In cows, mortality was significantly higher in spring than in summer, and increased with transport distance up to 300 km. A significant interaction between winter and long-distance transport was identified, resulting in the highest observed mortality (0.174%). In heifers, mortality exhibited no consistent seasonal or distance-related pattern, although the highest rate occurred at intermediate distances (51-100 km). Fattening cattle displayed low and stable mortality across all seasons and distances. In calves, the highest mortality occurred in summer (0.379%), with significantly lower rates in autumn and winter. No clear trend with distance or significant interaction effect was observed in this category. These findings indicate that season and transport distance significantly influence transport-related mortality, with the most pronounced effects in cows and calves. The identified risk patterns suggest a need for targeted interventions tailored to animal category, environmental conditions, and journey length to improve welfare during transport.