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Selenium In Nutrition REVISED EDITION Subcommittee on Selenium Committee on Animal Nutrition Board on Agriculture National Research Council NATIONAL ACADEMY PRESS Washington, D. C. 1983
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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the Na- tional Academy of Sciences, the National Academy of Engineering, and the Institute of Medi- cine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The National Research Council was established by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and of advising the federal government. The Council operates in accor- dance with general policies determined by the Academy under the authority of its congres- sional charter of 1863, which establishes the Academy as a private, nonprofit, self-governing membership corporation. The Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in the conduct of their services to the government, the public, and the scientific and engineering communities. It is administered jointly by both Academies and the Institute of Medicine. The National Academy of Engineering and the Institute of Medicine were established in 1964 and 1970, respectively, under the charter of the National Academy of Sciences. This study was supported by the Agricultural Research Service of the U.S. Department of Agriculture; by the Bureau of Veterinary Medicine, Food and Drug Administration of the U.S. Department of Health and Human Services; by Agriculture Canada; and by the Ameri- can Feed Manufacturers Association. Libras of Congress Cataloging in Publication Data National Research Council (U.S.) Subcommittee on Selenium. Selenium in nutrition. Bibliography: p. 1. Selenium in human nutrition. 2. Selenium in animal nutrition. I. Title. [DNLM: 1. Selenium- Metabolism. 2. Selenium-Toxicity. 3. Animal nutrition. QU 130 S467] QP535. S5N37 1983 ISBN 0-309-03375-6 Available from NATIONAL ACADEMY PRESS 2101 Constitution Avenue, NW Washington, DC 20418 612'.3924 83-8022 Printed in the United States of America
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Preface Early interest in selenium by nutritionists concerned its high concentration in certain range plants and the consequent toxicosis in animals that grazed those plants. More recently, the essential nature of selenium has become the center of attention, and this element is now known to be recluired by laboratory animals, food animals (including fish), and humans. Its role as an integral feature of glutathione peroxidase has been established, and other possible functions are under active investigation. This report reviews current knowledge concerning selenium in nutrition, including chemistry, distribution, metabolism, biochemical functions, de- ficiency signs, and effects of excess intake. For further background, the reader may wish to refer to the earlier reports of the National Research Council: Selenium in Nutrition (1971), Medical and Biological Effects of Environmental Pollutants: Selenium (1976), and Mineral Tolerance of Domestic Animals (1980~. The subcommittee is indebted to Philip Ross and Selma P. Baron of the Board on Agriculture for their assistance in the production of this report and to the members of the Committee on Animal Nutrition for their valu- able suggestions and reviews. Thanks are due Roger Sunde who was of special assistance to the subcommittee. Our thanks are also extended to Clarence B. Ammerman, Howard E. Ganther, Lonnie W. Luther, Walter Mertz, and James E. Oldfield for their constructive suggestions, and to Oscar E. Olson who reviewed the report for the Board on Agriculture. · . ~
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SUBCOMMITTEE ON SELENIUM DUANE E. ULLREY, (Chairman), Michigan State University GERALD F. COMBS, JR., Cornell University HARRY RUSSELL CONRAD, Ohio Agricultural Research and Development Center WILLIAM G. HOEKSTRA, University of Wisconsin KENNETH J. W. JENKINS, Canada Department of Agriculture ORVILLE A. LEVANDER, U.S. Department of Agriculture, ARS PHILIP D. WHANGER, Oregon State University COMMITTEE ON ANIMAL NUTRITION DUANE E. ULLREY, (Chairman), Michigan State University JIMMY H. CLARK, University of Illinois RICHARD D. GOODRICH, University of Minnesota NEAL A. JORGENSEN, University of Wisconsin-Madison BERYL E. MARCH, University of British Columbia GEORGE E. MITCHELL, JR., University of Kentucky JAMES G. Morris, University of California-Davis Watson G. POND, U.S. Meat Animal Research Center ROBERT R. SMITH, Tunison Laboratory of Fish Nutrition, USDI SIGMA P. BARON, Stalf Officer BOARD ON AGRICULTURE WILLIAM L. BROWN, (CHAIRMAN), Pioneer Hi-Bred International, Inc. LAWRENCE Bo G ORAD, Harvard University NEVILLE P. CLARKE, Texas A&M University Eric L. E~wooD, North Carolina State University ROBERT G. GAST, University of Nebraska EDWARD H. GLASS, Cornell University RALPH W. F. HARDY, E.I. du Pont de Nemours & Co., Inc. LAURENCE R. JAHN, Wildlife Management Institute ROGER L. MITCHELL, University of Missouri JOHN A. Piano, Rockefeller Foundation VERNON W. RUTTAN, University of Minnesota CHAMP B. TANNER, University of Wisconsin VIRGINIA WALB OT, Stanford University PHILIP Ross, Executive Director iv
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Contents 1 INTRODUCTION 2 CHEMISTRY Properties of Elemental Selenium Chemistry of Selenium-Containing Compounds Methods of Analysis 3 DISTRIBUTION Geological Distribution Commercial Sources Selenium in Soils Selenium in Plants Selenium in Animal Feedstuffs Selenium in Water Selenium in Human Foods Selenium Cycling in Nature 4 BIOCHEMICAL FUNCTIONS Nature and Properties of Glutathione Peroxidase Other Functions of Selenium Nutritional and Metabolic Interrelationships v 3 3 6 7 10 10 12 13 19 22 28 30 35 40 41 49 51
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vi METABOLISM Dietary Forms Absorption Vascular Transport Body Retention and Tissue Distribution Metabolism 6 NUTRITIONAL ASPECTS Dietary Requirements of Animals for Selenium Meeting Selenium Requirements for Animals Deficiency Signs in Animals Selenium in Human Nutrition EFFECTS OF EXCESS SELENIUM Selenium Toxicity in Laboratory Animals Selenium Toxicity in Farm Animals Selenium Overexposure in Humans 8 SELENIUM AND HUMAN HEALTH High Selenium Exposure Low Selenium Exposure 9 SUMMARY REFERENCES Contents 57 57 58 58 59 68 77 77 78 78 102 107 107 109 110 114 114 121 133 136
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Tables and Figures TABLES Atomic properties and electronic configuration of selenium Analysis of selenium Variation of selenium concentrations in various feed ingredients 4 Selenium content of selected foods of various countries 5 Estimated human daily intake of selenium from dietary sources 6 Concentrations of selenium in animal tissues in relation to level of dietary selenium 7 Average enzyme concentrations in wet swine tissue FIGURES 1 Generalized chemistry of selenium in soils 2 Regional distribution of forages and grain containing low, variable, or adequate levels of selenium in the United States and Canada 3 Cycling of selenium in nature 4 Some possibilities of biological cycling of selenium 5 Interrelationships of selenium, vitamin E, and sulfur · ~ amino aclc .s V11 4 7 27 34 36 62 91 16 24 37 38 55
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Selenium In Nutrition REVISED EDITION
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