1. Animal Diseases Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, Washington 99164
2. Programs in Vector-Borne Diseases and Genomics, Department of Veterinary Microbiology and Pathology and School for Global Animal Health, Washington State University, Pullman, Washington 99164
3. Division of Parasitology, Kimron Veterinary Institute, Bet Dagan 50250, Israel