The 3R principle is the fundamental ethical principle of laboratory animal science. Its aim is to reduce the frequency of animal experiments to what is absolutely necessary and to minimize the suffering of each individual animal as much as possible. This principle was anchored in the European Union Directive 2010/63/EU and is thus legally binding for all EU states (see above). The requirements of this EU directive were incorporated into German national law in 2013.
The 3R principle was established in 1959 by William Russel and Rex Burch in their book The Principles of Humane Experimental Technique (LINK).
What do the three Rs stand for?
Replacement: As far as possible, animal experiments should be replaced with alternative methods.
Reduction: Animal testing and the number of animals used should be reduced to the absolute minimum necessary.
Refinement: The stress on the animals during the experiment must be kept as low as possible and their housing conditions constantly improved.
How is the 3R principle implemented at the FLI?
Replacement – Avoiding animal experimentation
Whenever possible, scientific questions are first tested in cell culture (in vitro) before an animal experiment is planned and carried out (in vivo). Another approach is virtual experiments using computer models (in silico). To enable this type of experimentation, the Department of Bioinformatics at FLI has been further expanded. In addition, there is the possibility at the FLI to avoid animal experiments on vertebrates such as mice and fish by performing studies on invertebrate species such as nematodes or on fish eggs and larvae.
Reduction – Reducing the number of animals involved in experiments
In order to obtain meaningful results, a thorough experimental design is essential before the start of the experiment. In addition to advice from animal welfare officers, scientists at the FLI are required to consult biostatisticians. With the help of statistical methods, group sizes and the number of animals involved can be calculated in such a way that they produce meaningful results with the fewest subjects. Such careful experimental design helps to reduce the number of animals per experiment and, above all, to avoid repetition of animal experiments. In addition, a database has been programmed at the FLI that can be used to transfer animals between scientists at the FLI. For example, several scientific questions can be answered with the help of a single laboratory animal. This helps to keep the number of animals used as low as possible.
Refinement – Improvement of living conditions and treatment
Close cooperation between animal caretakers, veterinarians, researchers and animal welfare officers ensures that animals are optimally monitored and cared for in animal husbandry as well as in animal experiments. New approaches are regularly discussed and tested in the FLI Animal Welfare Committee (-> Animal Welfare at FLI, LINK). Thus, animal welfare at the FLI is being continuously improved.