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.1 It shares high homology with Helicobacter pylori, a gram-negative bacterium that is associated with gastritis, peptic ulcers, and adenocarcinomas in humans.2 Research over the last twenty years has focused on identification and isolation from stranded and captive cetaceans to develop effective diagnostic techniques, yet, questions remain regarding etiology of Helicobacter cetorum. It has been suggested that colonization of the glandular stomach lining may be involved in the development of gastritis in Atlantic bottlenose dolphins (Tursiops truncatus). It is largely unknown whether this colonization occurs as a primary infection or as a secondary opportunistic disease that infects compromised dolphins. The objectives of this proposed study are to analyze gastric tissues collected at FAU-Harbor Branch Oceanographic Institution between the years 2001 and 2008 from stranded Atlantic bottlenose dolphins in order to investigate the relationship between inflammation of the stomach mucosa and the presence of Helicobacter cetorum. Postmortem gastric tissue samples will be analyzed in order to determine if the presence of spiral-shaped bacteria and severe inflammation are linked. Analyses will include HE section, Giemsa stain, silver stain, and transmission electron microscopy. 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 stranded bottlenose dolphin populations in the Southeastern U.S.; and add to the growing knowledge of marine mammal health in coastal environments.
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. The authors thank the FAU-Harbor Branch Marine Mammal Dolphin License Plate Program for their financial support of this project, and Kenneth Kroell of the FAU-Harbor Branch Oceanographic Institution Marine Mammal Necropsy Laboratory for technical assistance.
References
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2. Marshall B. Helicobacter pylori: 20 years on. Clin Med. 2002;2(2):147–152.