David Baker Symposium
DAVID BAKER SYMPOSIUM
The technological advancement in production of crystalline amino acids has driven the cost of crystalline amino acids down significantly and facilitated the wide use of crystalline amino acids in food animal production. The primary reason of use of crystalline amino acids in animal's diet is to provide dietary essential nutrients for protein synthesis and to balance the diet and reduce dietary cost. Extensive researches with amino acids have greatly enabled such use. As a result, most swine diets today are formulated with 3 or 4 supplemental amino acids. However, the economical return on including beyond 4 supplemental amino acids becomes low and thus discourages the use of more than 4 supplemental amino acids for dietary saving purpose. The use of the functional role of amino acids might bear the new opportunity for amino acids. Tryptophan has unique physiological functions involving synthesize serotonin in the body. Increasing tryptophan intake is shown to elevate serotonin synthesis in the brain of pigs and reduce stress and improve performance of pigs under social stress. Research shows that methionine is used as a precursor of glutathione to protect intestinal mucosa from oxidative damages during weaning stress. Arginine, glutamine, and glutamate are shown to have functions in cell proliferation, potentially improving intestinal and immune function of nursery pigs and preventing loss of lean body mass in the sow. Leucine is a ketogenic amino acid. The carbon skeleton of leucine is converted to acetylCoA, which could be used for fatty acid synthesis in muscle tissue. Research showed that intramuscular fat was increased by feeding high dietary leucine levels. Overall, the different functions of individual AA beyond their roles as the building blocks for proteins give additional opportunities of amino acid application in animal production.