Abstract
The effect of dietary iron and/or protein deficiency on hemoglobin synthesis in growing rats has been investigated. Fifty-five female rats of the Donryu strain aged 3 weeks were divided into two groups and assigned diets supplemented with 20% or 5% casein. Each group was further divided into two groups, control and iron-deficient diet groups. The animals were maintained on these diets for three weeks, during which period body weight were recorded and blood samples were drawn in quantities of about 100μl via the tail vein for determination of the hemoglobin concentration (Hb), hematocrit (Ht), reticulocyte count and plasma protein content at weekly intervals. At the conclusion of the three-week observation period, some of the animals in each group were sacrificed by exsanguination via the axillary vein and the spleen, and liver tissue assayed for iron. Remainders in these group were fed thereafter on diets supplemented with iron or protein for a week to ascertain recovery from the dietary deficiencies. The folowing results were obtained:
1. Rats on the iron-deficient diets showed no appreciable change in weight gain from the respective control groups.
2. There were significant decreases in Hb and Ht of the rats fed on the iron-deficient diet with 20% casein as compared to the control group, whereas those maintained on the iron-deficient diet with 5% casein did not show any depression for these hematologic parameters. No significant intergroup differences were noted as to mean corpuscular hemoglobin concentration (MCHC).
3. The plasma and liver iron levels were lowest in the group on the iron deficient diet supplemented with 20% casein and the plasma iron level tend to be increased in the group on the diet with 5% casein supplementation.
4. The reticulocyte count decreased progressively in the growing rats. The iron-deficient diet group receiving 20% casein exhibited a rise in peripheral blood reticulocyte count and this trend was enhanced by dietary supplementation with iron. Dietary iron had on inf uence upon the reticulocyte count in the groups receiving 5% casein in feed, which showed elevation of reticulocyte count by administraion of 20% casein diet.
