Replacement of animals in research

Replacement is one of the "three Rs" (Replacement, Reduction and Replacement) of Russell and Burch, a concept which is described in more detail here.

They defined the three Rs as:

Replacement alternatives: methods which permit a given purpose to be achieved without conducting experiments or other scientific procedures on animals

Reduction alternatives: methods for obtaining comparable levels of information from the use of fewer animals in scientific procedures, or for obtaining more information from the same number of animals

Refinement alternatives: methods which alleviate or minimise potential pain, suffering or distress, and which enhance animal well-being

The PREPARE guidelines contain links to many resources which can be used to implement the 3Rs.

Methods to replace animal models (overview from the Swedish 3Rs Center)

The road to replacement (Genevieve Barr & Alice Carstairs, 2023)

The Rawle Report (2023), commissioned by the NC3Rs, concluded that, in the UK:

'Replacement does not seem to be covered well by any of the review processes. AWERBs and ASRU Inspectors rarely suggest use of replacements. They do not (and could not) have sufficiently detailed knowledge of the full breadth of the scientific areas they need to cover to know for every application whether appropriate and practicable replacement technologies are available.
AWERBs may assume that by the time a licence application is submitted to them for review the researcher and the funder have considered the options for replacement and concluded that animal use is necessary.

Funders’ peer review involves more specialist scientific expertise, but their review tends not to focus explicitly on whether suitable replacements might be available but rather on whether the applicants’ chosen models will allow them to answer the scientific questions posed.
Where the research is disease focused, the key question for peer reviewers is the relevance of the animal model to the human disease and how likely the results are to translate rapidly into clinical benefits. All funders require applicants to justify the need to use animals and their choice of species, but the extent to which this is challenged by reviewers varies between funders.'