The 3Rs concept
The Three Rs (Replacement, Reduction and Replacement) of Russell & Burch originated from a project initiated in 1954 by the Universities Federation of Animal Welfare (UFAW). The concept is described in detail in their book The Principles of Humane Experimental Technique, published in 1959.
Russell & Burch wrote:
They defined the three Rs as:
Replacement alternatives: methods which permit a given purpose to be achieved without conducting experiments or other scientific procedures on animals
Reduction alternatives: methods for obtaining comparable levels of information from the use of fewer animals in scientific procedures, or for obtaining more information from the same number of animals
Refinement alternatives: methods which alleviate or minimise potential pain, suffering or distress, and which enhance animal well-being
In 1999, 40 years after the publication of Russell & Burch's book, the participants at the 3rd World Congress on Alternatives and Animal Use in the Life Science endorsed the principle of the Three Rs in the form of the Declaration of Bologna (published with permission from the journal ATLA, Alternatives to Laboratory Animals):

Russell & Burch wrote:
The greatest scientific achievements have always been the most humane and the most aesthetically attractive,
conveying that sense of beauty and elegance which is the essence of science at its most successful.
conveying that sense of beauty and elegance which is the essence of science at its most successful.
They defined the three Rs as:
Replacement alternatives: methods which permit a given purpose to be achieved without conducting experiments or other scientific procedures on animals
Reduction alternatives: methods for obtaining comparable levels of information from the use of fewer animals in scientific procedures, or for obtaining more information from the same number of animals
Refinement alternatives: methods which alleviate or minimise potential pain, suffering or distress, and which enhance animal well-being
In 1999, 40 years after the publication of Russell & Burch's book, the participants at the 3rd World Congress on Alternatives and Animal Use in the Life Science endorsed the principle of the Three Rs in the form of the Declaration of Bologna (published with permission from the journal ATLA, Alternatives to Laboratory Animals):

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