Abstract

Gastric ulceration and associated clinical syndromes are identified as causes of morbidity and mortality in captive and wild cetaceans.^1,2 Proposed etiologies include parasitic infection, bacterial colonization, and high levels of gastric histamine.^3-5 The impact of gastric ulceration ranges from seemingly benign incidental findings to fatal perforation. While gastric ulceration is associated with morbidity in cetaceans, there are limited reviews of clinical presentations, diagnoses, and outcomes, and few reports of secondary abscess formation.

Two cases of gastric abscess secondary to gastric perforation in captive Atlantic bottlenose dolphins (Tursiops truncatus) were definitively diagnosed at necropsy. These individuals had a three-month (Case 1) and two-year (Case 2) history of illness. Major clinical signs included reduced feed intake and lethargy. Treatment during management included antibiotics, gastroprotectants, sedatives, and supplemental nutrition. Review of clinical pathology data showed that markers of inflammation such as white blood cell count, erythrocyte sedimentation rate, fibrinogen, and protein electrophoresis were relatively non-specific and often normal during clinical illness. In Case 1, major gross necropsy and histopathology findings included an abdominal abscess adjacent to the liver and stomach, erosions with bacterial colonization in the gastric mucosa, peritonitis, and acute multi-organ inflammation and necrosis. In Case 2, major gross necropsy and histopathology findings included a perigastric abscess approximately the size of the stomach complex with multiple smaller abscesses in the stomach wall and pancreas, peritonitis, and a stellate scar in the third gastric chamber considered consistent with a fully healed ulceration. There was no evidence of active ulceration at the time of necropsy. A definitive etiology for ulceration in both cases was not determined.

Acknowledgments

The authors would like to thank the animal care and veterinary staff at Indianapolis Zoo and National Aquarium in Baltimore for their dedication to the care of these animals.

Literature Cited

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