Abstract
Positive-contrast gastrointestinal imaging studies have been utilized in human and veterinary medicine since the early 1900s to detect diseases of the upper and lower gastrointestinal tract, but there is a paucity of literature on positive-contrast studies in marine mammals.1,2,3,4,5,6,7 This case series describes five bottlenose dolphins (Tursiops truncates), four cases and one control, that received barium sulfate 60% w/v via orogastric tube for positive-contrast radiography of the gastrointestinal tract. Standard radiography was performed with three dolphins, and fluoroscopy was performed with two dolphins. Barium sulfate doses ranged from 7–10 mL/kg. Radiographic imaging frequency was performed every 5 minutes postbarium administration and total imaging time was between 1–1.75 hours postbarium administration. One dolphin was administered barium 3 hours prior to initiating any imaging but was imaged every 5 minutes once radiography was performed. Gastrointestinal transit time was estimated to be between 3.75 and 7 hours based on two dolphins where barium was observed in the feces and in the colon radiographically, respectively. This is consistent with previously published information.8,9 Two dolphins were reported to have abnormal barium studies and were diagnosed with esophageal reflux. There were no gastric emptying or intestinal abnormalities observed in the imaging studies. Common radiographic findings in all cases included rapid gastric emptying within the first 10 minutes postbarium administration, linear parallel filling defects throughout the intestinal tract, and no barium present within the colon 1.75 hours postbarium administration. There were no adverse effects of barium observed.
Acknowledgements
The authors wish to thank the veterinary technicians and animal training staff over the years for the National Marine Mammal Foundation, U.S. Army, and Science Applications International Corporation for all their hard work and dedication to the animals in their care and their contributions in helping make these imaging studies happen.
*Presenting author
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