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Division of Nutrition, Food and Drug Administration, Department of Health, Education, and Welfare, Washington, D.C. 20204
The effect of a combined supplement (mg/kg diet) of 30 zinc, 5 copper, and 12 manganese on the long-term retention of cadmium was measured after feeding diets containing 115mCd and approximately 1 ppm cadmium to young Japanese quail (Coturnix coturnix japonica) for 7 days. The whole body retentions of 115mCd by birds fed the basal diet (BD) and the mineral supplemented diet (MSD) were 50.8% and 38.9% at the end of the 115mCd-feeding period, and 3.48% and 2.36%, respectively, 50 days later. The kidneys retained 0.95% and 0.62% and the livers contained 0.83% and 0.63% of the 115mCd ingested by birds fed the BD and MSD, respectively, 50 days after 115mCd dosing. The beneficial effects of the MSD were more apparent at the time of 115mCd intestinal uptake; however, the slopes of the retention curve of the birds fed the MSD indicated some beneficial effect of the zinc, copper, and manganese supplement on the long-term turnover of cadmium. These findings show that intestinal absorption and the ultimate accretion of cadmium by the liver and kidneys are significantly affected by supplementing the diet with moderate amounts of all three of the essential elements zinc, copper, and manganese. Because most of the beneficial effect of the MSD occurred at the time of absorption and initial uptake, the data suggest that nutritional status with regard to these three elements may not be so important as the relative composition of nutrients in foods that contain cadmium.
KEY WORDS: 115mCd cadmium zinc copper manganese long-term retention whole body retention Japanese quail
1 Taken in part from a thesis submitted by Richard M. Jacobs in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Biochemistry, University of Wisconsin, Madison, Wisconsin.
Manuscript received 12 September 1977.