Circular Feed Production and Consumption in the Context of Smart Animal Nutrition

Smart nutrition represents an innovation in farm animal nutrition and is one of the most promising ways to promote safe, high-quality animal products such as meat and milk, high animal welfare, and minimal impact on the environment. Smart livestock nutrition implies also the design of high nutritious diets for feeding animals in line with their needs and requirements. This goal can be achieved not only by selecting ingredients characterized by high nutrient density and digestibility, but also by looking for sustainable ingredients, including “circular” ingredients from waste and from nature. Using such alternative feed ingredients in the diet of farm animals is interesting for several reasons. Food leftovers are one way of converting losses from the food industry into ingredients for the animal feed industry, thereby keeping nutrients in the food chain. These materials can be extremely rich in carbohydrates, free sugars, and, depending on their origin, also in fats. Food leftovers, such as former food products (FFPs) and bakery by-products (BBPs) are subject to considerable processing including technological (milling, etc.) and heat treatments (cooking, extrusion, etc.). These impact not only the availability of nutrients and the kinetics of digestion but also on GIT/rumen health/functions and the animal response. FFPs and BBPs are safe from a microbiological point of view since; their microbiological loads are always below established tolerance levels. Using leftovers as feed also responds to the requirements of the circular economy. Understanding that food that is not suitable for human consumption is actually a resource rather than a waste product, our food industry can limit the amount of waste sent to landfill, thus saving costs and reducing the environmental impact of the food production chain. This approach can be considered a virtuous example of smart livestock nutrition and feeding that can and will become an option in sustainable animal production optimization.