Some animal creations require high energy consumption which leads to higher costs of the final products. If less expensive energy sources were used, this could provide significant increases in profits from livestock. In this regard, the use of dairy cattle manure for the generation of biogas is a promising alternative for the treatment of waste and reduction of the pollution potential and health risks of waste, with the additional advantage that the final effluent can be used as bio-fertilizer. The growing search for new and alternative sources for waste recycling and clean energy production points to the use of cattle manure as an economically viable option, given the importance of animal farming in Brazil. From the viewpoint of biogas production, our study has shown that anaerobic digestion at room temperature in tropical conditions using cattle manure as substrate is a viable technology. However, questions about the sustainability of the process were relevant, which takes into account the distribution of potentially pathogenic microorganisms and their susceptibility profile to antimicrobial drugs during the application of the bio-fertilizer in the soil. Towards continuing this line of research, advanced studies on the most appropriate way of using bio-fertilizer and its biosafety and environmental health should be conducted. The following institutions participated in the project: EMATER-MG (Corporation for Technical Assistance and Rural Extension of the State of Minas Gerais), EMATER-PR (Corporation for Technical Assistance and Rural Extension of the State of Paraná), Incaper (Capixaba Institute of Research, Technical Assistance and Rural Extension), ILCT-EPAMIG (Institute of Dairy Cândido Tostes – Agricultural Research Corporation of Minas Gerais), UFJF (Federal University of Juiz de Fora) and UNESP (Paulista State University “Júlio de Mesquita Filho”) – campus of Jaboticabal. The project strengthened the National Research Networks on Agro Biodiversity and Sustainable Agriculture - REPENSA/ Brazil.