Epsilon Archive for Student Projects

Abstract

Environmental enrichment is often described as important for pig welfare and natural behaviour. Despite this, the concept is defined differently between scientific studies, and it isn't always clear what distinguishes an enriched environment from a conventional environment. The aim of this study was to investigate how environmental enrichment is used in scientific studies on pigs published between 2005 and 2025. The study also examined which resources were described as enrichment, whether the enrichment was considered sufficient from an animal welfare perspective and how the results relate to Swedish animal welfare legislation. The study was conducted as a literature review including 40 scientific articles. The results showed that environmental enrichment was often described through the resources provided or the function of the enrichment rather than through clear definitions. Common forms of enrichment included straw, peat, sawdust and manipulable objects such as chains and ropes. Several studies reported positive effects on pig welfare, including increased natural behaviours and reduced harmful behaviours, although simpler forms of enrichment were often considered insufficient compared to substrate materials such as straw. The study also suggests that Swedish animal welfare legislation is relatively broad and open to interpretation regarding what should be considered sufficient enrichment for pigs. The study highlights that the lack of clear descriptions of reference environments in many studies makes it difficult to assess the actual effect of enrichment and to compare results across studies.