Before using animals in research, it is important to first consider whether any non-animal alternatives are available.
If no alternatives can be used, then the study should be designed to reduce the number of animals needed.
It is then important to reduce to a minimum any pain or distress that might be experienced by the animals that it is still necessary to use.
These concepts, of replacement, reduction and refinement were first proposed by Russell and Burch, in their book, “Principles of humane animal experimentation".
They have been incorporated into the national legislation of several countries and have become widely accepted by the international scientific community.