The need for more sustainable production and consumption of animal source food (ASF) is central to the achievement of the sustainable development goals: within this context, wise use of land is a core challenge and concern. A key question in feeding the future world is: how much ASF should we eat? We demonstrate that livestock raised under the circular economy concept could provide a significant, nonnegligible part (9-23 g/per capita) of our daily protein needs (~50-60 g/per capita). This livestock then would not consume human-edible biomass, such as grains, but mainly convert leftovers from arable land and grass resources into valuable food, implying that production of livestock feed is largely decoupled from arable land. The availability of these biomass streams for livestock then determines the boundaries for livestock production and consumption. Under this concept, the competition for land for feed or food would be minimized and compared to no ASF, including some ASF in the human diet could free up about one quarter of global arable land. Our results also demonstrate that restricted growth in consumption of ASF in Africa and Asia would be feasible under these boundary conditions, while reductions in the rest of the world would be necessary to meet land use sustainability criteria. Managing this expansion and contraction of future consumption of ASF is essential for achieving sustainable nutrition security.

No abstract

It is not known whether dietary guidelines proposing a limited intake of animal protein are compatible with the adoption of circular food systems. Using a resource-allocation model, we compared the effects of circularity on the supply of animal-source nutrients in Europe with the nutritional requirements of the EAT-Lancet reference diet. We found the two to be compatible in terms of total animal-source proteins but not specific animal-source foods; in particular, the EAT-Lancet guidelines recommend larger quantities of poultry meat over beef and pork, while a circular food system produces mainly milk, dairy-beef and pork. Compared with the EAT-Lancet reference diet, greenhouse gas emissions were reduced by up to 31% and arable land use reduced by up to 42%. Careful consideration of the feasible substitutability between animal-source foods is needed to define potential roles of animal products in circular human diets.

Many livestock and aquaculture feeds compete for resources with food production. Increasing the use of food system by-products and residues as feed could reduce this competition. We gathered data on global food system material flows for crop, livestock and aquaculture production, focusing on feed use and the availability of by-products and residues. We then analysed the potential of replacing food-competing feedstuff—here cereals, whole fish, vegetable oils and pulses that account for 15% of total feed use—with food system by-products and residues. Considering the nutritional requirements of food-producing animals, including farmed aquatic species, this replacement could increase the current global food supply by up to 13% (10–16%) in terms of kcal and 15% (12–19%) in terms of protein content. Increasing the use of food system by-products as feed has considerable potential, particularly when combined with other measures, in the much-needed transition towards circular food systems.

Dit onderzoek is uitgevoerd door Wageningen Environmental Research, Wageningen Economic Research en het Louis Bolk Instituut. Het werd gesubsidieerd door het Ministerie van Landbouw, Natuur en Voedselkwaliteit, in het kader van het beleidsondersteunend onderzoek en door detachering van de eerste auteur bij WEnR.

No abstract

A more circular food system is increasingly proposed to address the challenge of feeding a growing world population while limiting environmental impacts and resource use. A circular food system prioritises resources for direct food supply to avoid feed-food competition. The role of animals is to upcycle resources unsuitable or undesired for human consumption, so called low-opportunity-cost feeds (LCF) into animal-source food. This thesis evaluates the potential of various animals in upcycling LCF in a circular food system by applying an optimisation model that allocates available LCF to that combination of animals that maximise the supply of human digestible protein (HDP) to a EU-28 case study. We first explored the potential of common livestock species in the EU (e.g. pigs, laying hens, broilers, dairy cattle and beef cattle) under various productivity levels. Optimal use of LCF required livestock systems that had a high conversion efficiency (laying hens, dairy cattle), were best able to valorise specific LCF (dairy cattle for grass; pigs for food waste) and could valorise low quality LCF due to their low productivity. When, in addition, considering fishcurrently the only natural source of the essential eicosapentaenoic (EPA) and docosahexaenoic (DHA) ω-3 fatty acids-while demanding EPA/DHA requirements are met, fish provide nutritious food via both capture fisheries and fish farming. Even if capture fisheries rebuilds stocks and prioritises edible fish for human consumption, it can only fulfil 40% of EPA/DHA requirements. The farmed fatty fish needed to meet these requirements depend on fisheries by-products to meet their EPA/DHA requirements and livestock slaughter by-products to meet their high fat and protein requirements. A circular food system thus requires a combination of co-dependent animal production systems, tailored to the available LCF and the desired nutrient output. As the availability of food leftovers as LCF is currently restricted by legislation and other barriers, we explored the potential of food leftovers currently not used as LCF. Potential to increase animal protein intake was highest for, currently banned, household waste (+12%) and livestock byproducts (+18%) that are allowed in fish feed but currently not used and appear essential to meet human requirements of EPA/DHA ω-3 fatty acids in a circular food system. Improved use and legalisation of inevitable food leftovers can improve the resource use efficiency of both current and future circular food systems. When allowing all LCF in a circular food system, livestock and fish provide an HDP intake up to 39 g per capita per day, less than current animal protein supply but meeting 65% of total protein requirements. A circular food system, thus, requires a reduction in ASF consumption, and a change in the type of ASF we consume, where fish and milk become more prominent. While the used food systems approach illustrates the potential of animal production in a circular food system, it provides little direction to farmers in achieving sustainab...

Op weg naar een integrale meetmethode kringlooplandbouw 2 De KPI-K-systematiek 3 Wat is nodig om tot een werkende KPI-K-systematiek te komen? Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal Ken getal