Zebrafish are among the most widely used research animals globally, with welfare standards for their housing and experimental use having significant impact on millions of fish.
Zebrafish welfare in research settings is often inadequate despite legal protection — barren tanks with no social complexity, inadequate tank enrichment and poorly managed social groups are common. Fish are small, inexpensive and perceived as low-welfare priority compared to mammals, yet they have welfare needs that are easily addressed. Implementing the 3Rs robustly — reducing numbers where possible, refining experimental methods to reduce suffering, and replacing with non-animal models where available — is the primary welfare obligation.