Quantitative requirements of the hatchling green sea turtle for lysine, tryptophan, and methionine

The quantitative requirement for the amino acids lysine, tryptophan, and methionine was determined for the hatchling green sea turtle (Chelonia mydas). Hatchling green sea turtles were fed synthetic diets of purified substances with the composition of the diet varying in the amount of lysine, tryptophan or methionine present. The lysine requirement was found to be 4.8% of the crude protein (N X 6.25) or 1.7% of the dry diet. The tryptophan requirement was found to be 0.63% of the crude protein or 0.22% of the dry diet. The methionine requirement, in the presence of adequate cystine (3.1% of the crude protein), was found to be 1.5% of the crude protein or 0.49% of the dry diet.