1. Department of Pathobiology; Ontario Veterinary College; University of Guelph; Guelph; N1G 2W1; Ontario; Canada
2. Parasitology; IDEXX Reference Laboratories Ltd.; 1345 Denison St.; Markham; L3R 5V2; Ontario; Canada
3. Department of Biology; Acadia University; Wolfville; B4P 2R6; Nova Scotia; Canada