Abstract
The carcass of a recently deceased adult male Atlantic spotted dolphin (Stenella frontalis) was transported to the University of Florida for imaging and necropsy. A whole-body postmortem CT scan (virtopsy) revealed diffuse, bilateral pulmonary consolidation and multifocal, variably mineralized pulmonary nodules, which suggested that pyogranulomatous pneumonia was a possible cause of death. The main necropsy, cytological, and histopathological findings were severe, chronic suppurative fungal tracheitis and bronchopneumonia, as well as chronic meningoencephalomyelitis and gliosis with the presence of occasional intralesional protozoa and rare protozoal cysts. Aspergillus fumigatus was identified by PCR as the cause of the fungal pneumonia. Broad range consensus PCR for apicomplexan parasites and immunohistochemistry for Toxoplasma gondii performed on formalin-fixed paraffin-embedded brain were negative. PCR using broad range primers on frozen samples of brain and spinal cord identified Sarcocystis speeri. Although other Sarcocystis species have been documented in marine mammals, this is the first confirmed report of Sarcocystis speeri in a marine mammal species.1-8 The intermediate host of S. speeri remains unknown and the epidemiology is poorly understood.4-5 However, the presence of chronic meningoencephalomyelitis is suggestive that S. speeri may have been a causative agent for mortality in this S. frontalis, which could have acted as an aberrant host.8 Further investigations into the epidemiology, clinical relevance, and pathological significance of S. speeri as a potential emerging disease in marine mammals are warranted.
Acknowledgements
The authors would like to thank the Florida Fish and Wildlife and Conservation Commission for the funding of this work, as well as the staff of the Emerald Coast Wildlife Refuge for their initiative, time and collaboration with the transport and necropsy, and the Escambia Sheriff’s Department, Pensacola Beach Lifeguards, and the University of Florida’s Aquatic Animal Health program for their assistance with recovering the animal and investigating this case. The authors extend special thanks to Dr. Salvatore Frasca, April Childress, Dr. Andrew Allison, and the University of Florida’s Radiology Service faculty, Mary Wilson and the technician team for their time and contributions to virtopsy exams.
*Presenting author
+Student presenter
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