See Table 1 for the essential amino acids and their requirements for growing and finishing pigs. During digestion, protein breaks down into individual amino acids. The animal then absorbs amino acids from the intestines. Then, the amino acids are recombined within the body tissue into new protein molecules. When you formulate swine diets, keep in mind that most cereal grains are deficient in lysine, tryptophan and threonine.
Lysine is commonly the most limiting amino acid.
Evaluate protein sources primarily on the ability to correct these deficiencies, particularly that of lysine. See Table 2 for the approximate contents of some of the more important amino acids in common feeds. Sources of protein supplement. Soybean meal does an excellent job of supplementing cereal grains to meet the amino acid requirements of pigs. Other protein sources can be successfully included in the swine ration depending on their cost and quality.