The Iron Content of the Albino Rat at Different Stages of the Life Cycle

The normal iron contents of the bodies of albino rats at different ages, and in different conditions as to reproductive activity, are reported. The average iron content of rats at birth was found to be 0.0055 per cent. A decrease to 0.0026 per cent occurred during the suckling period. A pronounced increase, to 0.0045 per cent, took place between the ages of 20 to 40 days, after which only slight variations occurred. This increase in iron content apparently resulted from the taking of solid food. The absolute amount of iron present increased very slowly during the suckling period, but more rapidly thereafter, and at a rate closely proportional to the increase in body weight. The iron content of females was depleted through the growth of the litter during pregnancy; but the analysis of a single individual after the weaning of the young indicates that the iron content of the female returned to the normal during lactation.