Abstract
Helicobacter cetorum is a micro-aerobic, gram-negative bacterium that has been isolated from the lower gastrointestinal tracts of a variety of dolphins and whales.2 It shares high homology with Helicobacter pylori, a gram-negative bacterium that is associated with gastritis, peptic ulcers, and adenocarcinomas in humans.3 Little is known about the etiology of Helicobacter cetorum in cetaceans, however, it has been suggested that colonization of the pyloric regions of the stomach lining may be involved in the development of gastritis in Atlantic bottlenose dolphins (Tursiops truncatus). Questions exist whether Helicobacter cetorum colonization in the glandular stomach of bottlenose dolphins occurs as a primary infection that results from pollutants in the environment or as a secondary opportunistic disease that infects compromised dolphins. Research over the last twenty years has focused on identification and isolation from stranded and/or captive cetaceans to establish similarities between H. cetorum and H. pylori.2,3 This proposed study will investigate disease dynamics and the possible role that H. cetorum plays in the development of gastritis in cetaceans in order to develop a better understanding of etiology and causative agents gastritis in Atlantic bottlenose dolphins in coastal habitats. Analysis of gastric tissues collected at FAU-Harbor Branch Oceanographic Institution between the years 2001 and 2008 from dead stranded Atlantic bottlenose dolphins will be analyzed to investigate the relationship between inflammation of the stomach mucosa and the presence of Helicobacter cetorum. Diagnostic techniques shall include histopathology, light microscopy, sequencing using qPCR, and imaging using Scanning Electron Microscopy. Comparison of samples from known uninfected dolphins will be compared to samples from dolphins diagnosed with gastritis to determine if the presence of spiral-shaped bacteria and severe inflammation/ulceration are linked. Results from this study will help to establish the relationship between inflammation of the stomach mucosa and H. cetorum infection; discover trends in prevalence of gastritis and gastric ulcer disease in bottlenose dolphin populations in the Southeastern U.S.; and will support further research in etiology of Helicobacter infections as they pertain to marine ecosystem health.
Acknowledgements
The authors wish to thank Dr. Sentiel Rommel and Thomas D. Pitchford of the Florida Fish and Wildlife Conservation Commission, Dr. Michael Walsh formerly with Sea World of Florida, Mr. Wayne McFee and Dr. Pat Fair of the Center for Coastal Environmental Health and Biomolecular Research at Charleston, Dr. Forrest Townsend of Gulfarium, Drs. Martha Keller, Heather Lynch, and Mr. Alex M. Costidis of the Marine Mammal Pathology Laboratory in St. Petersburg, Florida for providing samples to the MMRC tissue bank for analysis in this study. The authors also wish to thank the entire staff at the FAU-Harbor Branch Marine Mammal Research and Conservation Center for their generous personal support and funding from the Dolphin License Plate Program. Last, thanks go to Necropsy Technician, Kenneth Kroell of the FAU-Harbor Branch Oceanographic Institution Marine Mammal Necropsy Laboratory for technical assistance.
* Presenting author
+ Student presenter
Literature Cited
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