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IACUC: Animal Alternatives

Audience: Principal Investigators, IACUC members, and IACUC support personnel

What is IACUC?

The US National Institute of Health's (NIH) Office of Laboratory Animal Welfare (OLAW) is directed by law to develop policies to ensure the safety and ethical treatment of animals in laboratories. To accomplish this mission, all institutions that pursue federally-funded research involving animals must have an Institutional Animal Care and Use Committee (IACUC). Where the Institutional Review Board (IRB) oversees human research, IACUCs oversee animal research.


To fulfill requirements set by the Animal Welfare Act and the Animal Care Resource Guide, maintained by USDA's APHIS, the principal investigator of federally-funded animal research must ensure alternative methods are explored to minimize animal pain and stress during experimentation. The PI must document this searching process in a literature review and include the dates of the searches performed, the time span covered by those searches, keywords and search strategies, and databases that were used during the search.

This guide has been constructed to help guide animal alternatives searches to accomplish literature searches.

The 3 Rs

The 3Rs concept refers to Reduction, Refinement, and Replacement of animals used in education and research. Initially developed over 60 years ago, this concept was described in Principles of Humane Experimental Technique, by doctors William Russell and Rex Burch.

The 3Rs can be more clearly defined by the following descriptions and on the NAL's Animal Welfare Information Center website:

Replacement: Technologies or methodologies replace or eliminate the need for animals in experiments. Full or absolute replacement avoids any use of animals, while partial or relative replacement methods require animal tissues, cells, or organs to be used in experiments conducted in vitro.

Reduction: This strategy relies on changes in experimental design to reduce the number of animals used in studies.

Refinement: Refinement methods reduce animal suffering, pain, or distress by altering their housing, husbandry practices, or experiments performed on them.

Searching to Improve Protocols

In order to reduce the pain and distress of animals while conducting studies, we must identify how current experimental protocols can be improved by incorporating elements of the 3 Rs. The types of protocols that may be improved are wide-ranging and include behavioral, neuropsychological, educational, training, or wildlife protocols.

While the processes of developing new protocols may vary based on institution, the literature review completed for IACUC ensures that the best available methodologies will be used during your study.

Your report documenting your literature must include several elements including:

  • The date searches were performed
  • The date range your search results include
  • A list of keywords used to search that cover scientific design, procedures of the study, and alternatives to the use of live animals
  • A narrative description of the literature review's findings and explanations why any alternatives that are found but not used are inappropriate for your study

The USDA's Animal Welfare Information Center maintains helpful resources on its site (opens in a new window) to aid researcher efforts.