Gordon R. Carter, DVM, MS, DVSc, is a Professor Emeritus of the Department of Biomedical Sciences and Pathobiology at the Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute, and State University in Blacksburg. Carter has published numerous scientific papers and is the senior author of more than a dozen textbooks. Dr. Darla J. Wise, MS, PhD, is an Assistant Professor of Biology at Concord College in Athens, West Virginia, and is the associate editor of Proceedings of the West Virginia Academy of Science. Wise’s research interest is in host-pathogen relationships. She has authored articles on immune responses, characterization of enzymes associated with host-pathogen relationships, and DNA-based methods of disease diag