The DSR model (OECD, 1996) basically helps to identify and understand the processes involved in livestock environment interactions. It focuses first on the human activities that create pressures (the earlier name was Pressure-State-Response Model), which are animal and crop agriculture, and related processing. These activities create positive or negative forces (for example methane emission, soil compaction, or improvement of soil structure through nutrient recycling), which change the quality and quantity of the natural resource base of air, water, soil, flora and fauna, and non-renewable resources. Information on the state of that resource base, reinforced or weakened by the valuation of the society of environmental values, leads to a societal response. Society responds to this information through environmental, general economic and sectoral policies. Changes in these policies will generally change the incentives to use certain technologies, for example, pollution mitigation, reduction of methane emission or positive synergies between livestock and wild-life. The model is especially suitable to guide the identification of the critical parameters to be used in an environmental impact assessment of proposed livestock projects and policies.
Linking these three major components of the DSR model are information linkages between pressures and responses, between the state and the pressures, and from the state to the response. These feedback mechanisms allow us the opportunity to better understand the consequences of policy and technology interventions. Therefore the PSR model blends well with the induced innovation model which is the second basic model used in conducting this study. More recently the OECD (OECD 1996) has introduced a more explicit conceptual model based on the same principles.