TABLE OF CONTENTS 



ACKNOWLEDGMENTS iii 



LIST OF TABLES vii 



LIST OF FIGURES ix 



ABSTRACT xi 



CHAPTER 1 



INTRODUCTION 1 



CHAPTER 2 



LITERATURE REVIEW 5 



Definitions of Trace Mineral Sources 5 



Trace Mineral Bioavailability 6 



Factors that Affect Trace Mineral 



Bioavailability 7 



Assessment of Trace Element Bioavailability . 8 

 Comparisons of Organic and Inorganic Trace Element 



Sources 9 



Zinc 9 



Absorption 11 



Transport and Tissue Uptake 11 



Bioavailability of Sources 12 



Copper 14 



Absorption 15 



Transport and Tissue Uptake 17 



Bioavailability of Sources 18 



Bioavailability of Other Trace Mineral 



Complexes 19 



CHAPTER 3 



RELATIVE BIOAVAILABILITY OF ZINC METHIONINE AND TWO 



INORGANIC ZINC SOURCES FED TO CATTLE 22 



Introduction 22 



Materials and Methods 23 



Results 26 



Discussion 31 



Implications 32 



Summary and Conclusions 32 



v 



