Millions of animals are used in scientific research annually; the 3Rs framework of Replace, Reduce and Refine aims to minimise their suffering while maintaining scientific progress.
Laboratory animal welfare has improved substantially since the 3Rs framework became embedded in regulation. Analgesic use has increased, housing standards have improved and humane endpoints have reduced prolonged suffering. However, regulatory requirements vary substantially between countries, and global research outsourcing sometimes exploits weaker welfare standards. Full implementation of the 3Rs remains uneven even in countries with formal requirements.