Enhancing pig welfare: exploring the effects of early socialisation in commercial pig farming (Sus scrofa domesticus)
Summary
In commercial pig farming, the process of weaning typically occurs between three and five weeks of age. Weaning under conventional circumstances is an abrupt process that involves a sudden separation of piglets from their mother, followed by grouping with unfamiliar conspecifics, dietary changes and relocation into high densities. This abrupt transition induces social and psychological stress, resulting in heightened aggression, abnormal behaviours and health issues among piglets. In recent years, there has been growing interest in on-farm strategies aimed at mitigating these negative effects of weaning. One of these strategies is early socialisation, where piglets are introduced to unfamiliar conspecifics before the weaning period begins. In this way, piglets develop the social skills needed during weaning. This review investigates the impact of early socialisation on various indicators of pig welfare in commercial farming settings. Specifically, we examine its effects on aggression, injuries, stress-related behaviours and physiological markers, fear, positive social interactions, health and performance, before, during and after weaning. The findings of this literature review confirm the positive impact of early socialisation in commercial pig farming. Notable benefits include reductions in aggressive behaviour, injuries, stress-related abnormal behaviours and physiological stress markers, alongside increases in positive social interactions, overall health and performance. Despite these advantages, many farmers remain hesitant to implement alternative housing systems because of concerns about potential economic losses due to reduced growth or increased mortality. Therefore, future research should delve deeper into the effects of implementing early socialisation practices and their implications for economic viability. By bridging the gap between economic interest and animal welfare, we encourage sustainable farming practices that prioritise pig welfare while ensuring economic viability.