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 available methods to improve the housing and the quality of life for animals and implement analgesic protocols effectively.
  • Clearly demonstrate the necessity of animal experimentation and the expected benefits while considering the constraints imposed on the animals (weighing up the interests).
  • Provide a justification for the choice of animal models, ensuring 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:

Reducing the number of animals used in each experimental protocol to the absolute minimum (Reduce)

  • Researchers collaborate with statisticians to determine the best experimental approach and the minimum of animals required.
  • The scientific community advocates for translational studies and the development of modern and non-invasive bioimaging methods.

Improving the welfare of experimental animals and minimizing stress (Refine)

  • Researchers must consistently use appropriate painkillers.
  • Whenever possible, less invasive techniques should be prioritized.
  • Proactive monitoring and documentation of animal welfare and the establishment of clear termination criteria should be carried out by well-trained experimenters.

Replacing animal use with alternative methods (Replace)

  • Preference should be given to cell-based models like human cell cultures.
  • Invertebrate models should be favored over vertebrate models.
  • The development and use of bioinformatics approaches should be encouraged.

Animal welfare

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

Housing conditions are strictly defined by law, ensuring that animals can exhibit natural behaviors. These conditions consider species-specific needs, such as the need to hide, nest or establish social interactions.

To avoid generating anxiety in animals, their adaptability should not be excessively challenged. This includes minimizing transportation, acclimating animals to human contact, reducing noise, enriching their environment, and providing appropriate lighting.

Veterinary monitoring of the animals and regular health checks are mandatory and subject to continuous oversight.

All institutional animal facilities are accredited by the cantonal veterinary authorities, which conduct annual assessments of working procedures, infrastructure, and housing materials.

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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