34 DPP Lecture: Evidence of methionine effects on health and immune response of animals

Abstract

Abstract Methionine is an essential amino acid that is commonly supplemented in livestock diets, including for swine and poultry. As with other amino acids, requirements for methionine have largely been based on maximizing growth performance; however, there is evidence that nutrient requirements, including for sulfur amino acids, are altered by immune status of the animal. As such, there has been significant interest in exploring the non-proteinogenic functions of amino acids and how these work to support animal health in addition to growth performance. While methionine has a key role in protein synthesis, it is involved in numerous biological functions, including participation in transsulfuration and transmethylation pathways, as a precursor of intermediates in metabolic pathways (e.g., carnitine, cystine), and in components of the immune response (e.g., acute-phase proteins), and in antioxidant status (i.e. glutathione, taurine). While undersupply and oversupply of methionine can lead to deficiency and toxicity, respectively, it is likely that supplementation with methionine above the current recommendations for growth would be beneficial for animal health, especially during times of stress or immune stimulation.