Abstract
An approximately 16-year-old, 123 kg, adult female bottlenose dolphin (Tursiops truncatus) was examined for acute anorexia. The dolphin had a history of intermittent gastrointestinal disease and progressive spinal abnormalities due to loss of tail flukes at a young age. On initial examination, the dolphin appeared to be floating higher in the water. No other clinical abnormalities were noted. Treatment was guided by routine diagnostic testing and included antibiotics, gastro-protectants, and fluid support, administered via gastric tube. After brief improvement, clinical signs worsened, and ultrasonography and radiography were performed. Peritoneal effusion and abnormally fluid-and gas-distended bowel with hypermotility were identified. After initial leukopenia, the animal developed neutrophilia with a degenerative left shift, hepatocyte damage, and evidence of cholestasis. Repeat ultrasonography revealed progressive intestinal dilation and development of GI hypomotility and tricavitary effusion. Surgical intervention was pursued, but the dolphin arrested during pre-operative catheter placement. Post-mortem examination revealed intestinal torsion with necrosis of a 145 cm segment of distal bowel. No histopathologic evidence of preexisting intestinal disease was found. Intestinal torsion has been documented in numerous species, including both managed care and wild cetaceans. It is considered fatal if not quickly corrected surgically.1–6 A rectal swab was positive for a novel Atadenovirus by PCR. Members of the genus Mastdenovirus have been identified in gastrointestinal samples of cetaceans7, but the clinical significance of this novel atadenovirus is still unclear.8 Abnormal abdominal cavity conformation due to kyphosis and unusual swim pattern may have predisposed the dolphin to torsion.
Acknowledgements
The authors would like to thank the incredible animal health and animal care staff at Clearwater Marine Aquarium. A special thanks to the veterinary surgical team for their expertise and advise with the case -Dr. Carolina Le-Bert, Dr. Dean Hendrickson, Dr. James Bailey, Dr. Michael Renner, and Dr. Stacy DiRocco.
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