Office of Research

Amino Acid Nutrition – Swine, Dairy, and Poultry

Amino Acid Nutrition

From the 1920s through the 1950s, the work of W.C. Rose in Biochemistry and H.H. Mitchell in Animal Sciences at the U of I demonstrated that certain amino acids (components of protein) were essential and crucial to the normal growth and health of mammals and birds.  The Animal Sciences Department has been the national leader in building upon these discoveries to improve  nutritional recommendations and the production of meat from pigs and poultry.

Dave Baker helped establish modern practices for formulating diets for amino acids and the use of crystalline amino acids as dietary supplements for farm animals.  Baker’s work in the 1990s established the concept of “Ideal Protein” in diet formulation. Jimmy Clark provided the largest data base on rumen microbial synthesis of amino acids in dairy cows that was used in the 2001 NRC model. Carl Parsons and Hans Stein continue to define “digestible amino acid” content of feeds used in pig and poultry diets to provide the largest database used in formulating diets by the production industry.

Stein’s recent research has shown that high-protein distillers dried grains can replace 100 percent of the soybean meal in a diet fed to finishing pigs without any effect on growth performance or carcass characteristics as long as the diets are fortified with crystalline lysine, threonine and tryptophan. When 70 percent of a swine producer's variable cost is attributed to feed, it is important that producers have options.  If corn and soybean meal are expensive, high-protein distillers dried grains can help lower feed costs.