Review: Nutrient and energy supply in monogastric food producing animals with reduced environmental and climatic footprint and improved gut health

With more efficient utilisation of dietary nutrients and energy, diversified production systems, modifications of diet composition with respect to feedstuffs included and the use of free amino acids, the negative impact of animal food production on the environment and climate can be reduced. Accurate requirements for nutrients and energy for animals with differing physiological needs, and the use of robust and accurate feed evaluation systems are key for more efficient feed utilisation. Data on CP and amino acid requirements in pigs and poultry indicate that it should be possible to implement indispensable amino acid-balanced diets with low- or reduced-protein content without any reduction in animal performance. Potential feed resources, not competing with human food security, can be derived from the traditional food- and agroindustry, such as various waste streams and co-products of different origins. In addition, novel feedstuffs emerging from aquaculture, biotechnology and innovative new technologies may have potential to provide the lack of indispensable amino acids in organic animal food production. High fibre content is a nutritional limitation of using waste streams and co-products as feed for monogastric animals as it is associated with decreased nutrient digestibility and reduced dietary energy values. However, minimum levels of dietary fibre are needed to maintain the normal physiological function of the gastro-intestinal tract. Moreover, there may be positive effects of fibre in the diet such as improved gut health, increased satiety, and an overall improvement of behaviour and well-being. (c) 2023 The Author(s). Published by Elsevier B.V. on behalf of The Animal Consortium. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

By improving feed utilization efficiency, using diversified production systems, modifying feed composition, and incorporating free amino acids, the negative impact of animal food production on the environment and climate can be reduced. Accurate understanding of nutrient and energy requirements for animals with different physiological needs and effective feed evaluation systems are essential for efficient feed utilization. Available data on protein and amino acid requirements in pigs and poultry suggest that balanced diets with low or reduced protein content can be implemented without compromising animal performance. Potential feed resources can be derived from traditional food and agro-industries, as well as emerging feedstuffs from aquaculture, biotechnology, and innovative technologies, which do not compete with human food security. However, the high fiber content in waste streams and co-products used as feed for monogastric animals may reduce nutrient digestibility and dietary energy values. Nonetheless, adequate levels of dietary fiber are necessary for maintaining normal physiological function of the gastrointestinal tract, and fiber might also have positive effects on gut health, satiety, and overall well-being.