Experimentation on non human animals is a widespread practice in our society and a main topic for animal ethics normative theories. In the last forty years the humanisation of such practice has been deeply influenced by the so called “3Rs method”. One of the most important aims of this method is the improvement of the welfare of the animals involved in experimental procedures through the Refinement of housing and experiment conditions. Far to be a merely technical concept, animal welfare is moral as well. The article tries to suggest an approach to animal welfare more complex than the mental state approach, which seems to be the most common one. Such new and richer approach is rooted in the utilitarian conception of good life elaborated by John Stuart Mill for human beings. Non human welfare (as that of humans) is promoted by conditions in which individuals can self develop themselves and try to achieve their own and particular good life. The article analyses also how such an approach can influence the practice of Refinement and suggests some further theoretical issues raising from this change of view toward non human welfare.
