1. Aquatic Animal Health Laboratory; Department of Pathobiology and Diagnostic Investigation; College of Veterinary Medicine; Michigan State University; 1129 Farm Lane, Room 177K East Lansing Michigan 48824 USA
2. Department of Fisheries and Wildlife; College of Agriculture and Natural Resources; Michigan State University; East Lansing Michigan 48824 USA
3. Michigan Department of Natural Resources; Fisheries Division; Post Office Box 30466 Lansing Michigan 48909 USA