Use of analgesia to refine fish experiments

Globally, millions of fishes are used in laboratories and they are the second most popular model used in regulated procedures in the European Union, with approximately 60,000 used in Sweden annually.

While most fish undergo anaesthesia during procedures that span the full range of severities including highly invasive surgery, analgesia (pain-relief) is not routinely provided.

The present proposal aims to address a key question to improve the welfare of animals in research: how to refine invasive experiments using fish by employing pain-relief?

This project will investigate the impact of a range of pain-relieving drugs on both larval and adult fish to identify which drugs at what doses are effective in providing pain-relief. We will investigate which agents prevent pain-related behavioural and physiological responses.

Further, the effects of these drugs on data collection to assess any confounding effects and pharmacokinetics will be assessed to guide scientifically informed and humane choice of pain-relief.

These findings will also assist in determining when to re-administer analgesia and inform the development of pain management protocols. This proposed project is a crucial step in refining experiments using fish on a global scale.

Employing analgesia during invasive techniques represents a major step forward in improving experimental zebrafish welfare as well as potentially reducing the severity of a large number of procedures.