Carp are the most widely farmed fish globally, central to Asian and European aquaculture, with welfare considerations around handling, transport, and the live fish trade.
Carp aquaculture is enormous in scale and yet receives relatively little welfare research attention compared to salmon and trout. The live fish trade creates specific welfare concerns, with carp transported and held in conditions that cause chronic stress before eventual slaughter. Handling during pond management, grading, and harvest causes measurable cortisol elevation and immune suppression. Slaughter methods for carp vary widely, with many operations using asphyxiation in air or ice slurry without prior stunning. Given the scale of carp production and the clear evidence for their pain sensitivity, welfare improvements in carp aquaculture would benefit more individual animals than improvements in any other farmed fish sector.