Atlantic salmon ( Salmo salar) is one of the most important export commodities in Norway. Future growth in the industry is expected, and global demand for Norwegian produced salmon is rising. Salmon is generally accepted as a sustainable source of protein, and several studies state that the carbon footprint of salmon is lower than for example beef, pork and poultry
. A majority of the carbon footprint of the salmon from farm to harvest is accounted for by the feed
. Feed for salmon produced in Norway has global and complex supply chains , with 92% of all ingredients imported in 2020
. An average for the last 10 years show that around 45% of ingredients in compound feed for livestock production in Norway were imported
. These global value chains can be vulnerable for political shifts , conflicts, epidemics as well as climate change. There is a national goal to increase the Norwegian self-sufficiency degree, and producing sustainable feed resources in Norway is a key component to succeed here. The SusFeed project, financed by the Norwegian Research Council (grant #326825) aims to increase raw material for feed produced in Norway and investigates the potential and sustainability of novel feed ingredien ts such as insects, microalgae, and grass fibres.
To investigate and assess the sustainability and robustness of the feed system, a holistic perspective on the feed system is needed. We aim to quantify the current supply chains of feed in Norway using M aterial F low Analysis (MFA)
. MFA is useful methodology to assess the resource efficiency of a system . A quantification and visualisation of the feed system with a MFA gives a deeper understanding of the current feed system , on the amounts of mass, protein and energy currently used and how new ingredients can increase the sustainability of the feed system .
The quantification of the current feed system is done based on the MFA methodology . The system boundaries are from feed ingredient to edible product of animal in Norway in 2020. Separate systems were made for salmon, cattle, pork, and poultry . The system was quantified for total mass of feed, protein, and energy in the feed. The MFA is based on numbers on total feed consumption and animal production from official statistics data sources
. Feed composition is based on average diets from the major feed producers for salmon
. Rest raw materials are calculated using conversion factors. Other inputs than feed and waste streams have not been quantified for this work. The systems are visualized using Sankey diagram in Python with the use of the plotly package
Results & Discussion
In a world with increasingly higher demand of food and animal-based proteins, sustainable supply chains are important to reduce negative environmental, social, and economic impacts . It is important that new ingredients fulfil the animal’s nutritional requirement , is produced in a sustainable manner and that resources are used efficiently. Therefor e, knowledge on the current feed system can help to identify where improvements can be done. Using MFA to quantify and visualize the feed system gives a great overview of the current resource utilization and efficiency. Our model also considers a protein and energy layer as well as the mass layer , giving an even more profound understanding of the system . This methodology is also useful to assess the suitability of new resources in terms of required amounts of mass, protein, and energy.
The visualisations show both how much ingredients are imported , and the degree of resource utilization based on feed ingredients into the system, compared to the amount of the edible product as output of the system. However, o ur work is based on the national feed system, which means our findings is not valid for individual producers, but our results do give indications of the current resource use and efficiency in the Norwegian feed system. New ingredients will change both the mass of ingredients, and the feed system as whole. We also identify that the degree of utilization of rest raw materials have great impacts on the e fficiency of the system.
Further work in the Susfeed project will analyse the resilience of new feed vale chains and the environmental impact of novel feed ingredients using a life cycle assessment and the socio-economic impacts using input-output modelling.