Author Affiliations +
D. O. TRAINER,1 F. F. KNOWLTON,2 L. KARSTAD3
1Department of Veterinary Science, University of Madison, Wisconsin 53706
2U.S. Department of Interior, Fish and Wildlife Service, P.O. Box 9037, Guilbeau Station, San Antonio, Texas
3Ontario Veterinary College, University of Guelph, Guelph, Ontario