Carp are the world's most produced farmed fish by volume, raised in Asia and Europe in a wide range of systems. Despite their scale of production, welfare standards for farmed carp remain poorly developed compared to salmon or trout.
Carp welfare suffers across multiple production stages. High stocking densities in ponds can trigger chronic stress, suppress immunity, and increase disease susceptibility. Dissolved oxygen management is essential: levels below 4 mg/L cause physiological stress and below 2 mg/L lead to mortality. Live transport in poorly oxygenated water, sometimes for days, causes exhaustion and injury. Slaughter methods commonly used in Asian markets — including chilling on ice, asphyxiation in air, or selling live for home slaughter — are likely to involve significant suffering given the high hypoxia and cold tolerance of carp, which can survive on ice for hours before losing consciousness. Percussive stunning followed by gill cutting offers a more humane alternative.