Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Animal Science


Proteins are defined as organic compounds formed as polymers of amino acids. The structural characteristics of the individual proteins enable them to act as catalysts (enzymes) and thus control the rate of all biological reactions, to serve as carriers for biologically important substances in the organism, to regulate physiological relationships as hormones, and to serve as structural components for subcellular, cellular and other organic substances. Previous research has indicated that for optimum utilization of amino acids to occur the required amino acids must be present at the site where synthesis of the organic substances takes place. These required amino acids must be present in the s8llle amounts and must be in the same ratios to each other as they are found in the organic substance to be formed. Ten of the approximately two dozen known amino acids are considered to be dietary essentials for swine. These ten amino acids cannot be synthesized by the pig or if synthesized their production is so meager that optimum growth cannot be supported. Therefore, they must be supplied in the diet. Cereal grains are of relatively “poor quality" and do not contain adequate amounts nor the correct balance of amino acids to support the optimum growth of growing and finishing swine. Considerable research has indicated that the most limiting amino acid in diets composed of cereal grains for monogastric animals is lysine. Soybean meal is considered to be a supplement of good quality for swine; however, methionine and lysine are considered to be limiting amino-acids. Most swine rations in the corn belt area are composed of corn and soybean meal plus the necessary minerals, antibiotics, and vitamins required to support optimum growth. Previous research at this station, however, has shown that rat ions compo sed predominantly of corn and soybean meal ·can often be improved with lysine supplementation to the drinking water of growing swine.. Reported herein are three experiments conducted to determine the value of supplemental lysine when added to the drinking water of growing and finishing swine fed a corn-soybean meal ration as measured by subsequent growth, feed conversion and changes in blood and serum components.

Library of Congress Subject Headings

Swine -- Feeding and feeds




South Dakota State University