Lack of Evidence for Stress Being Caused to Pigs by Witnessing the Slaughter of Conspecifics

The effects of witnessing the slaughter of conspecifics on the stress responses of pigs were investigated. Previously catheterized pigs were allowed to see the stunning and sticking (exsanguination) of pigs in a nearby pen. Heart rate was monitored and serial blood samples were taken to assess stress responses. Packed cell volume (PCV), Cortisol and β-endorphin were determined in the samples. In addition, behavioural observations and subjective assessments of animals’ responses were made. Although the levels of hormones, PCV and heart rate tended to be generally high due to handling, there were no specific increases in response to witnessing stunning and slaughter. These results suggest that witnessing the slaughter act does not distress pigs.