Slaughtering Atlantic salmon using stun-and-bleed vessels or well-boats and their subsequent effects on welfare and quality

This study evaluated the impact of two slaughter and transport methods on the welfare and product quality of Atlantic salmon reared at a land-based facility. One group was slaughtered at sea with a stun-and-bleed vessel (SBV), while another was transported by well boat (WB) with 3 days in a waiting pen and slaughtered on land. Two additional control groups were included: a chemically anaesthetized group (CG) and a minimally handled group (SCG) directly by the tank. Welfare indicators were evaluated in all groups, including welfare scores, blood parameters, rigor mortis development and muscle pH over 72 h post-mortem. Subsequently, the CG, SBV, and WB groups were packaged on ice and analyzed for comprehensive quality assessment, including texture, color, enzyme activity, sensory evaluation, and microbiological shelf life. Results indicated that SBV slaughter resulted in improved welfare outcomes compared to the WB group, indicated by slower rigor development, higher initial muscle pH, better welfare scores and lower stress-related blood markers. Nevertheless, product quality during chilled storage was comparable across groups. Therefore, these findings suggested that slaughter at sea with SBVs can lower physiological stress while maintaining product quality during storage. • Two slaughter and transport methods for Atlantic salmon were compared. • The stun-and-bleed showed improved welfare indicators than the well-boat group. • The stun-and-bleed group had lower stress-related blood parameters. • Product quality during chilled storage did not differ among groups.