**5. Conclusions**

In this review study, were summarised the primary reasons that affect the emission of NH3, N2O, CO2, CH4, H2S, odours and PM in housing, then analysed the consequences of these pollutants on birds, workers and environment, and finally discussed different best available techniques for environmental protection and sustainability of broiler production, particularly feeds and feeding management, feed supplements, litter management and treatment of exhaust air. Thus, broiler farms should select mitigation strategies based on several considerations, such as location, climate conditions, environmental policies and financial resources.
