[Effect of the placental barrier on iron levels in biological fluids and tissues of sows and their fetuses during pregnancy].

The investigation was carried out on 4 gilts and 29 pregnant sows (in the pregnancy period from 21st to 112th day) as well as their fetuses. The sows and their fetuses were divided into 4 groups with regard to the duration of pregnancy. Total iron binding capacity (TIBC) and unbound iron binding capacity (UIBC) were determined and percent of transferrin saturation was calculated in the blood serum of the sows and in the serum of umbilical blood as well as in amniotic and allantoic liquids. Iron centent in the uterus, placenta, liver, kidneys and spleen was determined by the method of atom absorption. The results were converted to 1 kg of dry matter of the organ. It was found that transferrin was not the only transporting form of iron in the fetuses of sows, though it was predominant in the majority of the examined fetuses. It can be assumed that other transporting form depends mainly on the saw itself and participates in Fe flow through placenta. It is still unknown if transferrin being present in amniotic and allantoic liquid explicitly originates from fetus. The organs revealing the highest contribution to iron mobilization during pregnancy seem to be spleen and then liver.