Developmental Changes in Serum Albumin, Transferrin, Iron, and Iron Binding Capacity of Growing Chickens and Egg-laying Hens

Abstract

The present study was carried out to clarify changes in serum albumin (Alb), transferrin (Tf), iron, and total and unsaturated iron-binding capacities (TIBC and UIBC) of growing chickens and egg-laying hens. Starch block electrophoresis was employed to purify serum Alb and Tf, and their levels were determined by the single radial immunodifusion test. The serum iron level, TIBC and UIBC were determined by the TCA precipitation method following atomic absorption spectrophotometry. Serum Alb increased rapidly from 1, 100mg/100ml to 1, 600mg/100ml during the first 3 weeks of age, it then increased slowly to 2, 200mg/100ml by 16 weeks of age, and thereafter maintained that level. Serum Tf level at hatching was 240mg/100ml, but then rapidly decreased to 100-130mg/100ml by 5 weeks of age. Thereafter it slowly increased until 25 weeks of age, showing 200mg/100ml in males and 300mg/100ml in females. Serum iron and TIBC decreased until 5 weeks of age; thereafter, they increased slightly in males, but in females increased rapidly until just before egg-laying, showing levels of 700μg/100ml and 820μg/100ml, respectively. There were significant differences between males and females in serum Tf and iron levels and TIBC. UIBC capacity re-mained almost constant during the growing period. The percentage of serum iron in females remained almost the same as that in males (35-55%) until 19 weeks of age, but it increased to 60-85% during egg-laying. It seems likely that serum Tf and iron levels and TIBC in chickens are closely related to egg-laying.