Robust assessment of the environmental footprint of animal products is essential to support and monitor efforts to reduce both the emissions intensity and resource demands associated with their production. Feed additives have the potential to confer environmental benefits in their use to support animal productivity, animal health, lifetime performance or even direct environmental benefits. The Food and Agriculture Organization (FAO) Livestock Environmental Assessment and Performance (LEAP) Partnership established various harmonized methods to assess the environmental footprint of livestock. This includes specific guidelines applicable to feed additives.

Set up of the study

For this study 14 nutritional interventions have been selected, including the use of feed enzymes, vitamins, carotenoids and eubiotics. Furthermore, the study focusses on three terrestrial target species: broiler chickens, dairy cows, and fattening pigs. The reference systems were Dutch and Belgian. The nutritional interventions, along with the FAO LEAP guidelines for feed additives, were documented through an extensive literature review and further translated into potential environmental effects observable at farm level.
Finally, the study has been reviewed externally and complies to the ISO 14044 LCA guidelines.

Using sector guidelines to evaluate environmental performance

Our methodological exploration verifies the applicability of sector LCA guidelines to evaluate nutritional interventions improving animal productivity, health, lifetime performance and emissions. Overall, the study confirms the potential of nutritional interventions, and feed additives in particular, to improve the footprint of animal production. Nevertheless, we also concluded that more detailed guidance and more consistency between the guidelines would be helpful. This ‘road testing’ study identified areas where the existing guidelines should be made more specific to provide more robust LCA outcomes. This was for instance the case in accounting variability and uncertainty when translating complex zootechnical dynamics into an LCA model. This also occurred in resolving changes in the production and composition of manure leaving the farm and for modelling nutritional interventions that act on product quality and following stages in the value chain. Furthermore, the study highlights the crucial role of feed formulations in determining estimated impacts. The way these dilemmas are managed by LCA experts may affect the outcome to a large extent, and therefore the need for clearer guidance.