Useful Links:
Dr. John King - Cornell: http://w3.vet.cornell.edu/nst/
University of Maryland Aquatic Pathology : http://aquaticpath.umd.edu/apg/toc.html
Penn State University Zebrafish atlas: http://zfatlas.psu.edu/
University of Iowa : http://www.path.uiowa.edu/virtualslidebox/vet_histopathology/content_index_db.html