Blueprint for research to detect loss of consciousness and/or sensibility of fish at slaughter

The rapid expansion of aquaculture has emphasized the urgent need for humane slaughter practices and reliable validation tools for the loss of consciousness. Many current methods, such as asphyxiation and live chilling, fall short of ethical standards due to prolonged fish suffering and poor outcomes. Gas immersion shows modest improvements but cannot yet be classified as humane. Electrical stunning holds potential, but its effectiveness is undermined by rapid recovery times and a lack of data validating its reliability under intensive culture conditions. Percussive stunning and central nervous system destruction is a better option but lack validation at commercial scales. Anaesthetics could reduce stress yet face regulatory and consumer challenges. Studies, especially on gilthead seabream and European seabass, highlight the importance of neurological assessments to evaluate stunning efficacy. The review stresses the need for rigorous, large-scale studies and collaborative efforts to refine techniques and set industry standards for ethical, humane fish slaughter.