CONTENTS 



Page 



Highlights 137 



Overview 137 



Objectives of Offsite Maintenance Efforts 137 



Breeding Programs v. Long-Term Cryogenic Storage 138 



Sampling Strategies 142 



Identification of Candidates for Conservation 142 



Preservation and Collection Considerations 144 



The Movement of Germplasm— Disease and Quarantine Issues 145 



Maintenance Technologies 148 



Storage Technologies 148 



Breeding Technologies 149 



Development and Utilization Technologies 156 



Needs and Opportunities 157 



Wild Animals 157 



Domestic Animals 159 



Chapter 6 References 163 



Tables 



Table No. Page 



6-1. General Guidelines for Intervention To Conserve 



Natural Populations 143 



6-2. Criteria for Classifying Domestic Breeds as Endangered 143 



6-3. Captive Animals Required for a Fixed Proportion of Genetic Diversity 



Over a Number of Generations 149 



6-4. Successful Artificial Insemination in Nondomestic Mammals 154 



Figures 



Figure No. Page 



6-1. Transcontinental Embryo Transfer 154 



6-2. Embryo Transfer Flowchart 155 



Boxes 



Box No. Page 



6-A. Breeds 138 



6-B. Replacement and Genetic Diversity 139 



6-C. Genetic Drift and Inbreeding 150 



6-D. Embryo Transfer 153 



6-E. Captive Breeding and Przewalski's Horse 156 



