Bacteriophages (or phages) are organisms that infect and destroy target bacteria. In recent years, bacteriophages have been postulated as alternative to antibiotics in aquaculture. At low scale, researchers have obtained very promising results, but utilization at industrial scale will require knowing the environmental impact of phages, especially on bacteria ecology. This project seeks to address this gap between laboratory and industrial scale treatment. Based on genetic technologies, this project will study the effect of bacteriophages on environmental and intestinal bacteria communities. This research is financed by the LIFE+ environmental programme of the European Commission and will go from 2014 until 2017.