Williams (1939) first isolated pantothenic acid as a growth factor for yeast. The vitamin was also investigated as a growth-promoting factor for lactic acid bacteria. Pantothenic acid is widely distributed in biological materials. Subsequent to its isolation as a microbial growth factor, it was shown that pantothenic acid is identical to an antidermatitis factor for chicks and a growth-promoting factor for rats. The presence of pantothenic acid as a component of coenzyme A indicated the vitamin’s biochemical role and led to the demonstration that pantothenic acid-deficient rats had defects in the ability to metabolize fatty acids.
Signs of pantothenic acid deficiency vary in different species. An effect on growth response usually can be demonstrated. Most pantothenic acid-deficient laboratory animals exhibit dermatitis, achromotrichia, and nasal porphyrin excretion. Pantothenic acid-deficient poultry exhibit a leathering disorder, fatty livers, and a characteristic dermatitis in the corners of the mouth.