Positive welfare: What does it add to the debate over pig welfare?

Since the beginning of the farm animal welfare debate half a century ago, the focus has been on the negative side of animal welfare, with most research studying the harms induced by modern husbandry to animals and how to prevent them. Here we review the trend of the last two decades to investigate what has become referred to as positive animal welfare. We present six published frameworks for positive welfare which draw from human positive psychology and the concept of quality of life. Next we describe animal-based approaches available to assess positive welfare in pigs and the limited data available on the current status of positive welfare in modern pig production. Finally, three areas are identified where a focus on positive welfare could set future trends in animal welfare research and implementation of better pig welfare on farms.