Utilization of Amino Acids from Foods by the Rat

Abstract
The per cent lysine utilized by the protein-depleted rat from purified proteins, animal protein products, cereal and legume foods was determined. On an over-all basis, the results indicate a greater utilization of lysine from dried eggs and skim milk (91%) and from fresh meats (84%) than from cereal and legume foods (71%) and cooked or processed meats (70%). The fecal excretion of lysine was determined, and the results showed that a greater amount of lysine was excreted in the feces of animals fed the cereal foods and unheated soybean flakes than of those fed other test products.