The dairy sector makes great efforts to improve its sustainability. The impacts of 15 options for improving sustainability were evaluated by means of a literature review. These options cover the aspects of productivity (milk yield per day of life), composition of the feeding ration (e.g. proportion of grassland and pasture forage), specific feed components (e.g. use of certified soya), animal husbandry (e.g. regular outdoor exercise), animal health (herd healthcare measures), biodiversity improvements (participation in a biodiversity improvement programme), and socio-economic aspects (e.g. multi-year contracts). Environmental (11 indicators), social (3 indicators) and economic (3 indicators) impacts were assessed. For some combinations of improvement options and indicators, an univocal assessment was achieved. Examples for an overall favourable effect were feeding of certified soya or herd healthcare measures. For several combinations, the literature provided controversial conclusions, where the effect depends on the context of the production system. Trade-offs between indicators occurred frequently, such as animal-friendly housing improving animal welfare, but also increasing ammonia emissions. Recommendations to improve some options are provided. Furthermore, tools for a quantitative sustainability assessment are suggested (e.g., life cycle assessment (LCA), product cost calculation, work budget calculation).
