Zebrafish have become one of the most used vertebrate research animals, with millions used annually in biomedical and behavioral research with limited welfare oversight.
Zebrafish welfare is significantly under-regulated relative to other vertebrate research models. Many jurisdictions do not extend welfare protections to larval zebrafish, despite evidence of pain sensitivity from very early developmental stages. Adult zebrafish are often housed in suboptimal conditions in large research facilities. The scale of zebrafish use means welfare improvements have large aggregate impact. Key welfare needs include appropriate social housing, environmental enrichment, water quality monitoring, and humane endpoints that prevent prolonged suffering in disease models.