1. Department of Veterinary Diagnostic Medicine, College of Veterinary Medicine, University of Minnesota, 1333 Gortner Avenue, St. Paul, MN 55108
2. Rivertown Animal Hospital, 5639 Memorial Avenue N, Stillwater, MN 55082
3. Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Minnesota, 1971 Commonwealth Avenue, St. Paul, MN 55108
4. USDA Agricultural Research Service, US National Parasite Collection and the Parasite Biology, Epidemiology and Systematics Laboratory, BARC East No. 1180, 10300 Baltimore Avenue, Beltsville, MD 20705