Diabetes-Like Metabolism in Healthy Bottlenose Dolphins (Tursiops truncatus)
IAAAM Archive
Stephanie K. Wong1; Sam H. Ridgway2
1U.S. Navy Marine Mammal Program, Space and Naval Warfare Systems Center, San Diego, San Diego, CA, USA; 2Pathology Department, School of Medicine, University of California, San Diego, La Jolla, CA, USA


Healthy Atlantic bottlenose dolphins (Tursiops truncatus) have been demonstrated to have a natural, prolonged glucose tolerance curve and a paradoxical increase in postprandial glucagon, similar to humans with diabetes mellitus.18,19 Previous studies conducted at the U.S. Navy Marine Mammal Program have also shown that the amount of glucagon released during the postprandial period in dolphins is dose-dependent with the amount of protein ingested (unpublished data). The evolutionary purpose for this metabolic process in healthy bottlenose dolphins may be to ensure readily-available blood glucose for a highly active brain during anticipated periods of fasting.3,6,7,11,15,20

To assess other blood-based changes that may occur during fasting and non-fasting states in bottlenose dolphins, a retrospective study involving 1,161 blood samples collected from 52 healthy animals during 1998-2005 was conducted to compare hematological and serum biochemical values in fasted versus non-fasted dolphins, controlling for age and sex. In addition to higher serum glucose levels, healthy dolphins fasted for 10 to 14 hours were more likely to have lower serum uric acid; higher platelet counts; and higher serum gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase compared to non-fasted dolphins. Similar changes have been associated with the level of glucose control in humans with diabetes mellitus.1,5,10,13,14,16,17,21 There is a need to further investigate potential associations between high protein doses and diabetes-associated syndromes, including uric acid nephrolithiasis2,9, hemochromatosis8, and chronic hepatitis12, in dolphin populations.


The authors would like to thank GS Patton and GL Searle for their early unpublished work on insulin and glucagon in bottlenose dolphins. We also thank the U.S. Navy Marine Mammal Program management and veterinary team for their support of this work.


1.  Andre P, Balkau B, Born C, Royer B, Wilpart E, Charles MA, Eschwege E. Hepatic markers and development of type 2 diabetes in middle aged med and women: a three-year follow-up study. The D.E.S.I.R. Study (Data from an Epidemiological Study on the Insulin Resistance syndrome). Diabetes. Metab. 31, 542-550 (2005).

2.  Cameron MA, Maalouf NM, Adams-Huet B, Moe OW, Sakhaee K. Urine composition in type 2 diabetes: predisposition to uric acid nephrolithasis. J Am Soc Nephrol. 17, 1422-8 (2006).

3.  Castellini MA, Costa DP, Castellini JM. Blood glucose distribution, brain size and diving in small odontocetes. Marine Mammal Science 8, 294-298 (1992).

4.  Cefalu WT. Animal models of type 2 diabetes: clinical presentation and pathophysiological relevance to the human condition. ILAR J. 47,186-198 (2006).

5.  Cho NH, Becker DJ, Ellis D, Kuller LH, Drash AL, Orchard TJ. Spontaneous whole blood platelet aggregration, hematological variables and complications in insulin-dependent diabetes mellitus: the Pittsburgh epidemiology of diabetes complications study. J. Diab. Comp. 6,12-18 (1992).

6.  Craik JD, Young JD, Chesseman CI. GLUT-1 mediation of rapid glucose transport in dolphin (Tursiops truncatus) red blood cells. Am. J. Physiol. 274, R112-119 (1998).

7.  D'angelo G. Evidence for an erythrocyte glucose transport system in the belukha whale, Delphinapterus leukas. Cetology 42, 1-9 (1982).

8.  D'Souza RF, R Feakins, L Mears, CA Sabin, GR Foster. 2005. Relationship between serum ferritin, hepatic iron staining, diabetes mellitus and fibrosis progression in patients with chronic hepatitis C. Alimentary Pharmacological Therapies 21:519-524.

9.  Daudon M, Traxter O, Concort P, Lacour B, Jungers P. Type 2 diabetes increases the risk for uric acid stones. J. Am. Soc. Nephrol. 17, 2026-2033 (2006).

10. Dura TT, Moya BM, Casero AJ. Renal hypouricemia in juvenile diabetes mellitus. Esp Pediatr 44, 425-428 (1996).

11. Goodwin RF. The distribution of sugar between red cells and plasma: variations associated with age and species. J. Physiol. 134, 88-101 (1956).

12. Hernandez C, J Genesca, J Ingasi Esteban, L Garcia, R Simo. 2000. Relationship between iron stores and diabetes mellitus in patients infected by hepatitis C virus: a case-control study. Medicina Clinica115:21-22.

13. Kaplan JR, Wagner JD. Type 2 diabetes-an introduction to the development and use of animal models. ILAR J. 47, 181-185 (2006).

14. Lee DH, Ha MH, Kim JH, Christiani DC, Gross MD, Steffes M, Blomhoff R, Jacobs DR Jr. Gamma-glutamyltransferase and diabetes--a 4 year follow-up study. Diabetologia 46,359-64 (2003)

15. Marino L. A comparison of encephalization between odontocete cetaceans and anthropoid primates. Brain Behav. Evol. 51, 230-238 (1998).

16. Maxwell DB, Fisher EA, Ross-Clunis H. 3rd & Estep, H.L. Serum alkaline phophatase in diabetes mellitus. J. Am. Coll. Nutr. 5, 55-59 (1986).

17. Nan H, Dong Y, Gao W, Tuomilehto J, Qiao Q. Diabetes associated with a low serum uric acid level in a general Chinese population. Diabetes Res. Clin. Pract. [Epub ahead of print] (2006).

18. Ridgway SH, Simpson JG, Patton GS, Gilmartin WG. Hematologic findings in certain small cetaceans. J. Amer. Vet. Med. Assoc. 157, 566-575 (1970).

19. Ridgway SH. In: Mammals of the Sea: Biology and Medicine (ed. Ridgway, S.H.) 590-747 (Charles C Thomas, Springfield, IL, 1972).

20. Ridgway SH, House D, Finneran JJ, Carder DA, Keogh M, Van Bonn W, Smith C, Scadeng M, Mattrey R, Hoh C. Functional imaging of dolphin brain metabolism and flow. J. Exp. Biol. 209, 2902-2910 (2006).

21. Sterner G, Carlson J, Eckberg G. Raised platelet levels in diabetes mellitus complicated with nephropathy. J. of Intern. Med. 244, 437-441 (1998).

Speaker Information
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Sam H. Ridgway, DVM, PhD

Stephanie K. Wong

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