Deposition and Alimentary Excretion of Phosphorus-32 in Steers on High Molybdenum and Copper Diets

Abstract

Jersey steers on high and low levels of molybdenum and copper were studied in regard to their capacity to deposit radioactive phosphorus, injected intramuscularly, in the principal tissues and organs of the body, as well as the distribution of the isotope in the contents of the various alimentary segments and in the feces and urine. The results were calculated as percent dose in the sample and as percent dose per 100 milligrams of total phosphorus present. The steers were slaughtered 40 hours after the administration of the isotope and values were obtained for the liver, heart, kidney, lung, pancreas, spleen, salivary, parotid and adrenal glands, brain, rib and femur, as well as for the blood and alimentary tissues and contents. The sodium molybdate supplement and the copper sulfate supplement markedly changed the pathway of phosphorus excretion from the partition usually found in cattle to one in which most of the phosphorus was excreted in the feces. The rate of phosphorus excretion was markedly increased when the molybdate supplement was given alone. Copper sulfate and sodium molybdate supplements given together resulted in less effect upon the pathway of phosphorus excretion than when given individually, but did result in slightly lower tissue phosphorus values than those found in the other animals. Copyright © . .