3R Principle & Animal welfare

3R - "Reduce, Refine, Replace"

The 3R principle is a concept introduced in 1959 that requires the application of humane principles in animal testing.

The application of this principle obliges researchers:

  • To use all the methods that improve the housing and the quality of life for animals and using all available analgesic protocols.
  • To demonstrate why animal experimentation is necessary and what are the expected benefits taking into account the constraints imposed on the animals (weighing up the interests).
  • To justify the choice of the animal model used after making sure that no alternative methods are possible.

The lemanic institutions are firmly committed to promoting the application of the 3R principle in animal experimentation, as follows:

By limiting the number of animals used in each experimental protocol to the strict minimum (Reduce)

  • Researchers work in collaboration with statisticians in order to define the best experimental approach and the number of animals needed.
  • The scientific community promotes translational studies and the development of modern and non-invasive bioimaging methods.

By improving the welfare of experimental animals and minimising animal stress (Refine)

  • Researchers should systematically use appropriate painkillers.
  • The least invasive techniques have to be always privileged.
  • Animal welfare should be proactively monitored and documented and appropriate termination criteria should be established by well-trained experimenters.

By replacing the use of animals with other so-called alternative methods (Replace)

  • Cell-based models such as human cell cultures should be preferred.
  • Invertebrate models should be preferred to vertebrate models.
  • The development and use of bioinformatics approaches should be encouraged.

Animal welfare

Animal welfare is the priority of the staff responsible in animal facilities

The housing conditions are strictly defined by law and are established in such a way that the animal can behave as in its natural environment. These conditions take into account the behaviour of species such as the need to hide, to nest or to establish social interactions.

The ability for animals to adapt should not be overly solicited in order to not generate anxiety in the animals housed. For example, this involves limiting transport, getting the animals used to the people working with them, reducing noise, enriching the environment and dimming the lights.

Veterinary monitoring of the animals and the establishment of their health check is compulsory and is subject to permanent monitoring.

All institutional animal facilities are accredited by the cantonal veterinary authorities, responsible for checking the working procedures, infrastructure and housing material every year.


The Principles of Humane Experimental Technique (W.M.S. Russell and R.L. Burch)


Russell and Burch's 3Rs Then and Now: The Need for Clarity in Definition and Purpose








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