1. Department of Companion Animal and Special Species1 and
2. Department of Microbiology, Pathology and Parasitology, Center for Gastrointestinal Biology and Disease,2 College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina 27606;
3. Division of Digestive Diseases and Nutrition, Department of Medicine and Center for Gastrointestinal Biology and Disease, School of Medicine, University of North Carolina– Chapel Hill, Chapel Hill, North Carolina 27599-70803; and
4. Departments of Surgery and Microbiology, University of Wisconsin, Madison, Wisconsin,4 and
5. Department of Immunology, DNAX Corporation, Palo Alto, California5