The ‘One Nutrition’ approach: connecting crop production, animal nutrition and human nutrition

Animal feed is the largest single cost item in livestock production, accounting for 60%-85% (depending on the farm species) of the total cost inputs per year. Various ingredients are used to produce feed, most of which are not currently consumed by humans. However, production of food for humans and of feed for animals compete for the same resources, interfering with one another. The use of biomass as an energy source aggravates this competition. The feed industry must then enhance the efficiency of livestock production by reducing Greenhouse Gas (GHG) emissions and other factors that have a negative environmental impact. Thus, the use of natural resources must be reduced by increasing their reuse and using “circular” feed sources. Insects, single cell proteins (SCPs), seaweed, and former foodstuff products (FFP) are some interesting alternative nutrient sources for feed and are expected to help replace conventional nutrient sources. From a circular economy perspective, feeding these materials to livestock could be an effective option for increasing efficiency and environmental sustainability in the agri-food chain. Thus “circularity” and “One Nutrition” in agri-food production are key concepts to identify sustainable solutions for human nutrition and for the nutrition of food-producing animals. Raising food-producing animals as part of a circular food system allows the retention of nutrients in the food system. This paper addresses current and future challenges for sustainable animal nutrition, focusing on the following issues: (1) feed-food competition; (2) the concept of circular feed; (3) innovative, alternative sources for livestock nutrition; (4) water issue.