Organ culture of limb buds from riboflavindeficient and normal rat embryos in normal and riboflavindeficient media

Embryonic limb cultures from control and riboflavin‐deficient galactoflavin‐treated rats were explanted on gestation day 12.5 and grown in vitro for seven days. The riboflavin‐deficient limb buds failed to grow in riboflavin‐deficient medium but exhibited near‐normal protein synthesis and increase in size in medium supplemented with riboflavin. The growth of control limb buds was not impaired by exposure to deficient medium. The conclusion is that the major mechanism for production of limb defects functions at a local cell level rather than these resulting from physiologic impairment of the embryo.