TRANSFERRIN MESSENGER-RNA IN RELATION TO LIVER IRON STORAGE IN FARMEDATLANTIC SALMON (SALMO-SALAR)

Transferrin mRNA in liver was quantified in farmed Atlantic salmon (Sa lmo salar) fed three different levels (310-, 65-, and 40 ppm) of dieta ry iron for 26 weeks. At the time of sampling, the fish fed 40 ppm iro n showed symptoms of iron deficiency. Mean values of liver storage iro n was reduced from 84 to 12 mg kg(-1) and plasma iron from 2.3 to 1.6 mg l(-1) compared with fish fed 310 ppm iron. No significant differenc e in transferrin mRNA was observed between normal and iron deficient s almon; the amount of Tf mRNA was not related to the amount of stored i ron, either in groups or individual fish. This suggests that there is no iron-modulated transcriptional regulation of liver Tf expression in salmon as there is in chickens and rats.