The 3Rs

First defined back in 1959, the 3Rs are guiding principles for animal research used across the globe. They underpin policies, regulations and laws in the UK and many other countries.

Replacement

Replacement is the use of techniques which does not involve animals. This includes scientific and technological developments, such as computer modelling. It also includes the use of human volunteers and research using cells and tissues. The use of invertebrates such as fruit flies (Drosophila) and nematode worms, instead of higher animals also comes into this category, as it is not currently thought that these simple creatures can experience suffering.

Refinement

Refinement is the development of processes that decrease the stress or suffering of animals. This includes not only experimental techniques but also the care, feeding, housing and welfare of animals in facilities. Examples include finding the best anaesthetic for each species or simply getting animals used to being handled.

Reduction

Reduction involves minimising the number of animals used through efficient experiment design. For example, taking repeated samples from one animal throughout a process (if this does not increase the animal’s suffering) rather than euthanising a series of animals at different stages of the process. Collaboration and sharing of data also contribute to reduction.