According to the Institutional Animal Care and Use Committee Guidebook…

There is increasing public interest in exploring alternatives to the use of animals in biological research and testing. IACUCs regularly consider the question, "Is there an alternative to using live animals in this proposal?" Some suggest that the only acceptable alternatives are those that completely replace animals, while others have less restrictive definitions. The definition of alternatives that allows a degree of common understanding was developed by Russell and Burch, and is referred to as the three "Rs"- replacement, refinement, and reduction. For this discussion, the term "alternatives" refers to systems that do not employ whole live animals.

Alternatives to the use of animals include in vitro model systems. For example, isolated organ preparations, such as the perfused heart, represent in vitro models. More commonly, in vitro systems are thought of as cell, tissue and organ cultures. The source of the tissue may be primary tissue or cell lines obtained invasively or non-invasively. Tests have been developed using in vitro systems for the evaluation of cytotoxicity, inflammation, genotoxicity, and target organ toxicity among others. A third alterative is the use of nonbiological models systems. These include chemically-based systems, physical models such as hemodynamic flow chambers or computer simulations. More mechanistic models are being developed such as quantitative structure-activity responses, linear modeling relationships, and three dimensional computation models. As more data become available, an expansion in this area is anticipated.

Listed below are helpful resources that provide additional information on alternatives:

AGRICOLA AGRICultural OnLine Access: Bibliographic database of citations to publications and resources encompassing all aspects of agriculture and allied disciplines, including animal and veterinary sciences, entomology, plant sciences, forestry, aquaculture and fisheries, farming and farming systems, agricultural economics, extension and education, food and human nutrition, and earth and environmental sciences. Coverage 1970-present.

Altweb (Johns Hopkins) Provides a search engine to find information on alternative procedures.

Center for Animal Alternatives (UC-Davis)

CRISP Computer Retrieval of Information on Scientific Project: Contains research projects supported by the PHS, NIH, NIMH, NIAA. Includes current and past projects. Coverage 1972-present.

PubMed Citations and abstracts for articles published in journals in medicine, life science and health administrations.

NAL Animals Use Alternatives Thesaurus Produced by the US National Agricultural Library, this site provides a classification of terminology relating to alternatives and animal welfare.

TOXLINE National Library on Medicine's extensive collection of online bibliographic information covering the biochemical, pharmacological, physiological, and toxicological effects of drugs and other chemicals.