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Animal Alternatives Information

Resources for finding animal alternatives in laboratory research and educational settings.

Why Are Animal Alternatives Important?

The US Animal Welfare Act (AWA) regulations (specifically the 1985 Amendment), require the principal investigators to consider alternatives to procedures that may cause more than momentary or slight pain or distress to the animals, and provide a written narrative of the methods used and sources consulted to determine the availability of alternatives.

The search for alternatives refers to the three Rs described in the book, The Principles of Humane Experimental Technique (1959) by Russell and Burch. The 3Rs are reduction in the number of animals used, refinement of techniques and procedures to reduce pain or distress, and replacement of animals with non-animal techniques or use of less-sentient species.

The 3 Rs

Replacement means that animals should not be used at all if the same research, teaching or testing aim can be achieved in other ways. So the first question scientists must ask themselves at the planning stage of a study is "Do I need to use animals at all?" If the answer is "Yes" then Reduction and Refinement must be applied.


Reduction means keeping the number of animals used to the minimum necessary to achieve the research, teaching or testing purposes of the work. This avoids using unnecessarily large numbers of animals, but it is equally important to avoid using too few animals. If not enough animals are used it will not be possible to interpret the results, and the animals used would have been wasted. So the second question scientists must ask is "What is the lowest number of animals needed for this work?"


Refinement refers to keeping any pain, suffering or other harm which may be caused as low as possible for each and every animal used in the work. This means that every aspect of the work must be reviewed carefully and great care taken to minimize any noxious effects on the animals. Thus, the third question scientists must ask is "How can I minimize the pain or distress of every aspect of this work?"