Fish are increasingly recognized as sentient animals requiring proper anesthesia during research procedures. Improving fish anesthesia practices is a significant welfare opportunity in laboratory science.
For decades fish were assumed to be insensible to pain, justifying minimal welfare oversight in aquatic research. Evidence now confirms fish nociception, stress responses, and behavioral indicators of pain. This has driven regulatory changes in many jurisdictions requiring anesthesia for invasive procedures. However, implementation varies widely, and many labs lack expertise in fish anesthesia monitoring. Proper dosing, assessment of anesthetic depth, and attentive recovery monitoring are critical welfare improvements achievable without major cost.