A recent scientific study published in Aquaculture has provided new insights into how slaughter and transport methods affect the welfare and product quality of Atlantic salmon , one of the most important species in global aquaculture.

As the industry continues to expand and operations become more centralized, the findings arrive at a critical moment for producers managing longer transport distances and increasingly complex logistics.

Key Findings

The research compares two widely used approaches: at-sea slaughter using stun-and-bleed vessels and traditional well-boat transport followed by land-based processing .

The results point to clear welfare advantages when slaughter is carried out offshore:

• Improved welfare indicators in fish processed at sea
• Lower physiological stress levels , suggesting better overall condition
• Slower rigor mortis development , which can influence product consistency
• Comparable quality during chilled storage , indicating no commercial disadvantage

These findings suggest that reducing handling and transport time can positively influence both animal welfare and processing outcomes.

A graphical illustration of the timeline of the experiment. The figure was created in created in BioRender. Chan (2026) https://BioRender.com/nt9d6u4.  Click on the image to enlarge

Industry Implications

With aquaculture production valued in the billions of US$ globally , maintaining consistent quality while addressing welfare concerns is becoming increasingly important.

Longer transport durations expose fish to additional handling and environmental stress, which can affect not only ethical standards but also product quality, shelf life, and reliability for buyers.

Experimental setup for the welfare assessment of welfare scores, blood measurements, rigor mortis, and pH. 

The study highlights that the final stage before slaughter is a critical control point for both welfare and economic performance.

Industry Perspective

Companies such as Optimar are already developing technologies aimed at improving fish handling across the production chain.

According to Optimar , “Efficient and welfare-oriented stun-and-bleed processes contribute to reduced stress levels and more controlled processing conditions.”

Experimental setup for the quality assessment. SVG and TOS represent Nofima in Stavanger and Tromsø, respectively. For the control group, sampling was done on day 2 at Stavanger and day 5 at Tromsø.

The research reinforces a broader industry shift toward integrating welfare-focused practices as a key component of modern seafood production, balancing efficiency with sustainability and quality.

Read the full study

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

Chan et al., 2026 – Aquaculture