Abstract
Hemochromatosis, or iron storage disease, is a well-documented disorder in Atlantic bottlenose dolphins (Tursiops truncatus).1,5 A small population of Pacific white-sided dolphins (Lagenorhynchus obliquidens) exist in managed collections, and there are few publications regarding their diseases. An adult, female L. obliquidens at the Shedd Aquarium demonstrated a three year history of increased liver enzymes - alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and slowly increasing serum iron concentration along with decreased unsaturated iron binding capacity (UIBC). The dolphin had a history of mild weight loss and chronic waxing and waning exfoliative dermatopathy. Diagnosis of hemochromatosis was made after repeated findings of UIBC values of 0 µg/dL and complete serum iron saturation (100%). Previously, veterinarians with the US Navy Marine Mammal Program had successfully treated T. truncatus with hemochromatosis using repeated therapeutic phlebotomy to reduce whole body iron stores.2 The affected dolphin at Shedd was treated over a two month period with repeated therapeutic phlebotomies targeting removal of 10% of circulating blood volume3 per session. These induction sessions resulted in normalization of UIBC and serum iron concentration for two years before therapeutic phlebotomy was once again required. This is the first documented case of iron storage disease in a L. obliquidens. While historical hemochromatosis in cetaceans has been linked to nutritional iron supplementation, iron is no longer routinely included in cetacean nutritional supplements and the cause of more recent cases remains unknown. Current research is being conducted to determine if dietary consumption of iron differs between wild and managed T. tursiops populations.4
Acknowledgements
The authors wish to thank the Animal Health and Marine Mammal Department staff members at the John G. Shedd Aquarium for their support of this work and their dedication to animal care. The authors also wish to thank Dr. Shawn P. Johnson and the United States Navy Marine Mammal Program.
*Presenting author
+Student presenter
Literature Cited
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