The intervention runs over again the tormented developments of the rule about the legal protection of animals, starting from the principal stages of the scientific and philosophical reflections upon animals' subjectivity: the discoveries induced by ethology and animals' psychology, on the one hand, that consented to recognise animals as centres of assignation of a sphere of interests quantitatively and qualitatively connected with their more or less complex level of subjectivity; on the other hand the reflections upon "animals' welfare" und upon "the ethics of respect" developed about the conception of person, interest and right. Moving in this ambit we analyse the evolution of the rules that, starting from the first formulation of the crime of ill-treatment of animals (in the criminal code of 1930), saw the sensibility of the legislator getting more and more refined (thanks also to an impulse given by European Community or international acts) with the introduction of new instruments of protection in the different fields of utilization of animals (experiments, breeding, slaughtering and so on); but it saw also an enduring "habit" of compromise, in reference to the considerable economic or simple entertaining interests that concern the human activities where animals are used.
