Anesthesia for fish during handling and procedures is increasingly recognized as an essential welfare tool, though adoption remains inconsistent across aquaculture operations.
The use of anesthesia in fish handling is a clear welfare improvement that is both scientifically justified and practically achievable. Evidence strongly indicates that fish experience nociception and stress during handling, with measurable physiological consequences including elevated cortisol, immune suppression, and behavioral changes. Routine procedures in aquaculture - sorting, vaccination, weighing, sampling - cause repeated stress events for millions of fish. Industry adoption of anesthesia protocols remains inconsistent, often due to cost or convenience rather than scientific consideration. Regulatory requirements and consumer pressure can drive faster adoption of this welfare-improving practice.