Should we worry about the overuse of antibiotics in industrial animal farming ? As bacteria develop resistance to antibiotics, physicians today are faced with infections which are difficult to treat effectively, and which represent a serious public health threat. Resistance develops mainly from inappropriate use of antibiotics in humans or animals. You can actually find that one bacteria of human origin, which was never exposed to antibiotics, could pick up that resistance by having it transferred from another bacteria of animal origin that had been exposed to antibiotics. For this reason, the EU strictly regulated the uses of antibiotics in agriculture. Based on research in microbiology, bacteriology, sociology of public problems and science studies, this paper will study the story of antimicrobial resistance in animals discoveries. This paper will also examine the main factors underlying its politisation – the ‘Swann report’ and the ‘mad cow crisis’ – and the recent development of new policies. The governance promoted the participation of actors. It is double-sided. Experts and decision-makers are closest to the problem, but the influence exerted by interest groups is growing.