Laboratory Animal Welfare Reform: Progress and Remaining Challenges

The welfare of animals used in biomedical research has improved significantly through the 3Rs framework, but substantial challenges and suffering remain.

Key Facts

Approximately 192 million animals are used in research globally each year, with mice comprising the majority
The 3Rs framework — Replace, Reduce, Refine — was developed in 1959 and remains the dominant welfare framework
Replacement: switching to non-animal methods including cell culture, organoids, and computer modelling
Reduction: using statistical methods and sharing data to minimize the number of animals per experiment
Refinement: improving housing, procedures, and endpoints to minimize pain and distress in animals still used
Severity classifications — mild, moderate, severe, non-recovery — are required in EU research under Directive 2010/63/EU
Significant proportions of animal experiments still involve moderate or severe suffering in some research areas
Many researchers lack adequate training in refinement techniques that could reduce suffering within existing protocols

Welfare Considerations

Laboratory animal welfare reform represents one of the areas where systemic change is possible through regulatory and scientific leadership. The 3Rs framework has driven genuine progress: millions of fewer animals are used today than decades ago, and housing and husbandry standards have improved significantly in regulated jurisdictions. However, significant suffering persists, and replacement technologies have not yet fully substituted for animals in many research areas. The welfare gap between what is possible and what is standard practice — in terms of refinement techniques, humane endpoints, and housing enrichment — represents an ongoing challenge. Researchers, institutions, and regulators all have roles to play in closing this gap through training, incentives, and accountability.

What You Can Do

Support funding for non-animal research methods including organoids, organ-on-chip, and AI-based models
Advocate for mandatory training in refinement techniques for all researchers working with animals
Support animal care and use committees that take a proactive rather than minimum-compliance approach to welfare
Engage with organizations such as the NC3Rs that develop and promote 3Rs alternatives
Advocate for transparency in animal research through mandatory reporting of animal numbers and severity
Support policies that require demonstration of the 3Rs in grant applications for animal research funding
Learn about the regulatory frameworks governing animal research in your country and advocate for stronger standards