Abstract
Nine sheep were divided into three groups, three sheep in each. Each group was given a ration containing respectively 0.1, 0.6 and 1.2% calcium. The dietary calcium level was adjusted by the addition of calcium carbonate. From the 30th and the 60th day after the beginning of trial, urine, fecal and serum samples were taken for seven days. After a 67-days feeding period, two sheep from each group were sacrificed, and the livers and spleens were examined to determine trace mineral concentrations. The amount of all trace minerals excreted via urine were too little to affect the mineral balances. There was no significant difference in serum mineral concentrations among treatment groups. Fecal excretion of iron and copper significantly increased and retentions of these trace minerals became negative when the highest calcium ration was given. Liver iron and copper concentrations did not consistently alter, but spleen iron and copper showed a decreasing trend as the dietary calcium was increased. It may be possible that iron and copper requirements increase when a high level of calcium carbonate is given to cattle and sheep.
