Comparative Hematology during Deficiencies of Iron and Vitamin A in the Rat

Abstract

Male weanling rats were used in three experiments to study the hematologic response during deficiencies of iron and vitamin A, or both deficiencies together. In the first study 24 animals were divided into four groups and fed an iron-low, vitamin A-low, iron- and vitamin A-low, or a control diet. Iron deficiency resulted in hypochromic microcytic anemia, whereas vitamin A deficiency produced hypochromic microcytic polycythemia. A normocytic hypochromic anemia developed in animals deficient in both iron and vitamin A. Growth retardation occurred in all deficient animals. In order to determine whether iron absorption was impaired in vitamin A deficiency, the retention of radioactive iron was tested at three levels of vitamin A supplementation. Under these conditions iron absorption and retention were inversely related to vitamin A intake. This was thought to be a reflection of increased hematopoiesis produced by vitamin A deficiency. In a third experiment the effect of limited resupplementation of either iron or vitamin A to animals deficient in both iron and vitamin A was tested. Iron supplementation produced a direct positive response in growth and red blood cell counts whereas the limited vitamin A supplement produced delayed decreases in growth and red cell number. These data suggest that vitamin A and iron are interrelated factors in hematologic responses of the rat.