Occurrence of Pantothenic Acid
The distribution of this vitamin is so widespread in nature that little comment is required.
It is important, however, to understand that in large degree pantothenic acid is found in natural products in bound forms. Yeast, liver, and eggs are outstanding sources. Some meats, skim milk, and sweet potatoes contain moderate amounts of the vitamin, while most other vegetables and fruits have considerably less. Zook and associates reported the pantothenic acid content of a large number of foods using newer methods which release bound forms of the vitamin.
Requirements of Pantothenic Acid
Chicks require a dietary source of pantothenic acid, although laying hens get along and continue to lay eggs on diets containing very little of the vitamin. The eggs produced under these conditions are poor in hatchability and in fact reach a level of zero in this respect. A careful study of the pantothenic acid requirement for laying hens indicates that about 650 Ilg per 100 g of ration is sufficient for the production of eggs of high hatchabiltiy. It is interesting that for considerable periods of observation only about 150 Ilg per 100 g of ration is sufficient for maintenance of the adult chicken.
The requirements for various other species are more or less established. The human requirement is largely unknown. Estimates of 10 to 15 mg per day seem to be met easily even with diets classed below optimum. The estimates lack significance because of the man~ unknown factors, such as the degree of release of the bound vitamin in the intestinal tract and the amount of intestinal bacterial synthesis of the vitamin as well as the availability of this source. Goldsmith and others reported that high-cost 3000 Cal diets contained 5 to 11 mg of free and 13 to 19 mg of total pantothenic acid, while low-cost 2500 Cal diets contained 4 to 12mg free and 9 to 20 mg total vitamin. Normal adults excrete 1 to 7 mg of pantothenic acid in the urine daily.
