IRON IN RUMINANT NUTRITION

Abstract

SUMMARY The concentrations of total liver storage (non‐haem) iron, of the forms of this iron, and of plasma iron and total iron‐binding capacity, were determined in healthy adult sheep and cattle of both sexes. Individual variability in total non‐haem liver iron and in the water‐soluble (presumably ferritin) and water‐insoluble (haemosiderin) fractions of this iron was found to be high in both sexes of both species. Differences between the sexes were not significant but total storage iron and ferritin iron levels were significantly higher in sheep than in cattle. From two‐thirds to three‐quarters of the total storage iron occurred in water‐soluble form. This was assumed to be ferritin, although attempts to isolate this compound were unsuccessful. Plasma iron and total iron‐binding capacity concentrations and percentage saturation values were found to be of the same order as those found previously for sheep and cattle and for other species. Evidence was obtained that plasma iron concentrations and percentage saturation values are significantly higher in ewes than in rams.