Relation of skin lesions in the rat to deficiency in the diet of different B2-vitamins

A NOTICEABLE feature about the earlier studies of the " dermatitis " occurring in rats when they are deprived of the heat-stable B-vitamins has been the ir- regularity of its incidence. The occurrence of two different types of skin lesions developing under these conditions was foreshadowed in earlier work [Chick & Roscoe, 1928, p. 795; Chick & Copping, 1930, p. 933] and has been more clearly demonstrated in recent investigations. As the members of the vitamin B2 complex have gradually been separated from one another, and since vitamin B1 has been available in the purified state, it has been possible to use basal diets supplemented with relatively pure preparations of one or other constituent [see Gy6rgy, 1934; Chick et al. 1935; Copping, 1936].