1 Department of Clinical Studies, New Bolton Center, University of Pennsylvania, 382 W Street Rd, Kennett Square, PA 19348.
| 2 Present address is 530 Hilton Rd, Cochranville, PA 19330.
| 3 Department of Pathobiology, New Bolton Center, University of Pennsylvania, 382 W Street Rd, Kennett Square, PA 19348.
| 4 Present address is the Animal Disease Research & Diagnostic Laboratory, Veterinary Science Department, South Dakota State University, Box 2175, N Campus Dr, Brookings, SD 57007-1396.
| 5 Department of Clinical Studies, New Bolton Center, University of Pennsylvania, 382 W Street Rd, Kennett Square, PA 19348.