Anesthesia in fish reduces stress and pain during husbandry and research procedures, improving both welfare and data quality.
Fish experience stress and likely pain during handling procedures. Anesthesia immobilizes fish and reduces physiological stress responses, improving outcomes for both animal and researcher. Selection of appropriate agent, concentration, and exposure time is critical; overdose causes mortality and underdose leaves fish partially conscious. Training aquaculture staff in correct anesthetic use and providing access to approved agents represents a practical welfare improvement achievable at modest cost.