The recognized "animal welfare" includes five freedoms: freedom from hunger and thirst, comfort from pain and disease, freedom from fear and sadness, and freedom to express nature. In experimental animals, it is difficult for human beings to fulfill the five freedoms at the same time, and damaging their health is often the only process of research. At present, it is recognized that the balance between animal suffering and scientific research desire is the 3R principle, that is, refinement, reduction and optimization.
The "3R" principle of animal experiment is:
1. Reduction refers to the scientific method of obtaining the same amount of experimental data with a small number of animals or obtaining more experimental data with a certain number of ground animals in scientific research.
2. Substitution refers to the substitution of other methods for experiments or other research topics conducted by animals in order to achieve certain experimental purposes. Or it is a scientific method to replace conscious living vertebrates with unconscious experimental materials in the past.
3. Refinement refers to a scientific method to improve animal welfare by improving conditions, being kind to animals, or improving experimental procedures and techniques on the basis of scientific principles, so as to avoid or alleviate pain and anxiety unrelated to experimental purposes.