Developmental changes in serum ferritin of piglets

Serum ferritin concentration of 40 nursing piglets was measured by a two-site immuno-radiometric assay to assess relationships of serum ferritin to Fe-related blood characteristics and nonheme Fe concentration of the liver. Hemoglobin concentration rapidly decreased after nursing to 55% of the birth level at 2 to 4 wk of age when the piglets exhibited severe symptoms of Fe deficiency. However, an im injection of 1 ml of iron-dextran (100 mg Fe) at 3 d of age restored the hemoglobin level to near the concentration of 10 g/100 ml by 2 wk of age. Serum ferritin concentration was low at birth and 1 d of age, but increased by 3 d of age. From 1 wk of age onward, serum ferritin level of the unsupplemented animals decreased linearly and declined to the lowest level at 3 wk of age. With iron-dextran injection, however, systemic concentration of ferritin peaked at 1 wk of age and decreased linearly to 3 wk of age. Serum ferritin of both groups was almost depleted at 3 to 4 wk of age. Although a single injection of 100 mg Fe from iron-dextran is adequate to maximize weight gain and to maintain normal hemoglobin level, serum ferritin concentration was almost exhausted after 2 wk of age. Serum ferritin concentration of both groups increased gradually from 4 wk of age, followed by a quadratic rise to 8 wk of age. The elevation of serum ferritin of the unsupplemented group after 4 wk of age almost paralleled that of hemoglobin concentration.(ABSTRACT TRUNCATED AT 250 WORDS)