1. From the Section of Ophthalmology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, Pennsylvania;
2. the Department of Internal Medicine and
3. the Section of Comparative Medicine, Yale School of Medicine, New Haven, Connecticut;
4. Neurotech USA, Lincoln, Rhode Island; and
5. the J. A. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York.