Investigation of the Use of Biomarkers for Antemortem Diagnosis of Cardiac Disease in Marine Mammals
American Association of Zoo Veterinarians Conference 2019
Melissa J. Joblon1,2, DVM; Jennifer E. Flower1, DVM, MS, DACZM; Laura A. Thompson3, PhD; Kathleen E. Biddle4, DVM, DACVP; Deborah A. Burt4, BS; Natalie Rouse5, MS; Carrie E. Goertz5, MS, DVM; Kristen Jetzke6, LVT; Richard P. Giovanelli4, BS; Allison D. Tuttle1, DVM, DACZM
1Department of Animal Care, Mystic Aquarium, Division of Sea Research Foundation, Inc., Mystic, CT, USA; 2Animal Health Department, New England Aquarium, Boston, MA, USA; 3Research Department, Mystic Aquarium, Division of Sea Research Foundation, Inc., Mystic, CT, USA; 4Pfizer, Global Research and Development, Groton, CT, USA; 5Veterinary Services, Sea Life Center, Seward, AK, USA; 6Veterinary Services, Georgia Aquarium, Atlanta, GA, USA


Cardiac pathology, though extensively documented in marine mammals;1-5 remains difficult to diagnose ante-mortem. Cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (proBNP) are used in many species as sensitive and specific biomarkers for a range of cardiac diseases. This study aimed to determine whether cTn and/or proBNP were increased in confirmed cases of cardiac disease in beluga whales (BW) (Delphinapterus leucas), sea otters (SO) (Enhydra lutris), Steller sea lions (SSL) (Eumetopias jubatus), and California sea lions (CSL) (Zalophus californianus), compared to controls. Existing immunoassays for cTnI and proBNP were validated utilizing species-specific heart lysate spiked serum. Banked serum samples from animals with confirmed cardiac disease on histopathology (disease: BW n=3, SO n=4, SSL n=4, CSL n=19), and animals with no evidence of cardiac disease (control: BW n=5, SO n=2, SSL n=6, CSL n=6) were analyzed. Serum concentrations of cTnI (ng/ml) and proBNP (pmol/L) ranged as follows: BW: cTnI <0.03–21.06, proBNP <200; SO: cTnI <0.03–0.24, proBNP <200; SSL: cTnI <0.03–12.14, proBNP <200–1,783; CSL: cTnI <0.03–44.5, proBNP <200–1,871. Preliminary statistics revealed significantly higher proBNP in diseased CSL (Mann Whitney U test; p=0.017), and a trend toward higher cTnI in diseased SO (Mann Whitney U test; p=0.06). Higher cTnI in diseased animals was seen in other species; however, due to the presence of outliers statistical significance cannot be confirmed. Results suggest that proBNP and cTnI may be clinically useful as ante-mortem diagnostic tools in CSL and SO, respectively. Increasing sample size and further investigation regarding disease severity is warranted and in process.


The authors thank the Wild Animal Health Fund (WAHF) for providing generous funding for this project. We would also like to thank Sion Cahoon and Dr. Martin Haulena from Vancouver Aquarium, Barbie Halaska and Dr. Cara Field from The Marine Mammal Center, Natalie Rouse and Dr. Carrie Goertz from Alaska Sea Life Center, and Gayle Sirpenski from Mystic Aquarium for their support and invaluable contributions to this study.

Literature Cited

1.  Fonfara S, Sundermeyer J, Sorrosal DC, Weber C, Rosenberger T. Usefulness of serum cardiac troponin I concentration as a marker of survival of harbor seal (Phoca vitulina) pups during rehabilitation. J Am Vet Med Assoc. 2016;249(12):1428–1435.

2.  Kreuder C, Miller MA, Lowenstine LI, Conrad PA, Carpenter TE, Jessup DA, Mazet JA. Evaluation of cardiac lesions and risk factors associated with myocarditis and dilated cardiomyopathy in southern sea otters (Enhydra lutris nereis). Am J Vet Res. 2005;66(2):289–299.

3.  Kreuder C, Miller MA, Jessup DA, Lowenstine LJ, Harris MD, Ames JA, Carpenter TE, Conrad PA, Mazet JA. Patterns of mortality in southern sea otters (Enhydra lutris nereis) from 1998–2001. J Wildl Dis. 2003;39(3):495–509.

4.  Scaglione FE, Bollo E, Pregel P, Chiappino L, Sereno A, Mignone W, Moschi R, Garibaldi F, Tittarelli C, Guarda F. Heart pathologies in dolphins stranded along the northwestern Italian coast. Dis Aquat Organ. 2013;25;107(1):31–36. doi: 10.3354/dao02672.

5.  Zabka TS, Goldstein T, Cross C, Mueller RW, Kreuder-Johnson C, Gill S, Gulland FM. Characterization of a degenerative cardiomyopathy associated with domoic acid toxicity in California sea lions (Zalophus californianus). Vet Pathol. 2009;46:105–119.


Speaker Information
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Melissa J. Joblon, DVM
Department of Animal Care
Mystic Aquarium
Division of Sea Research Foundation, Inc.
Mystic, CT, USA

Animal Health Department
New England Aquarium
Boston, MA, USA

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