Mortality during Transport of Pigs Subjected to Long Journeys: A Study in a Large European Abattoir

SIMPLE SUMMARY: Animal welfare during transport is a topical issue, also considering that a large number of animals intended for farming and slaughter are transported every day along roads and highways throughout Europe to meet market needs. Besides the well-known animal welfare concerns, conditions encountered during transport also have considerable consequences on the industry’s profitability. Few studies have analysed the effects of long journeys on both animal welfare and economic losses. The present study aimed to propose the use of transport mortality (dead-on-arrival animals, or DOAs) and data collected routinely by the slaughterhouses and the Public Veterinary Services during inspections as a simple and systematic screening method for identifying problematic journeys or transport conditions. These data allowed us to observe a similar mortality rate compared to other studies carried out in Europe (0.09%) and to identify a significant increase in mortality during the hot season and when prolonged stops (>60 min.) were carried out during long journeys. Based on this case study, routinely collected data may therefore be used as a simple screening method for identifying problematic journeys or transport conditions. ABSTRACT: To date, especially in Europe, few studies have analysed the implications of long journeys on pig welfare and economic losses, expressed in terms of transport mortality. This study retrospectively analysed data collected from slaughtering registers and travel journals in a large Italian abattoir. We focused on pig transports coming from abroad and arriving at the slaughter plant after long journeys (a total of 59,982 pigs over 370 journeys). We explored the relationship between mortality and the following variables: country of origin, journey duration, astronomical season, stocking density on the truck, number of stops, and prolonged stops during the journey (lasting more than 60 min, likely due to traffic jams or truck problems). Overall, the low mortality rate observed (0.09%) was in line with European estimates. The factors with a significant or tendential effect on mortality during transport were the astronomical season (p = 0.0472, with higher mortality in spring) and the presence of prolonged stops during the journey (p = 0.069, tendential effect). Journey duration, stocking density, country of origin, and the number of stops were not statistically significant. In conclusion, based on this case study, using transport mortality combined with data collected during the common routine activity by the Public Veterinary Services in slaughterhouses could be a simple screening method for identifying problematic journeys or transport conditions.