Abstract

Hematology can be a useful diagnostic tool for evaluating systemic health in many species and can provide valuable information into the presence of underlying inflammatory disease; however, reptilian hematology is often unreliable since the reptilian patient may exhibit a leukocytosis, leukopenia, or normal leukogram during times of infection and/or inflammation.^5,6 Thus, there exists a need to develop more reliable methods for diagnosing and monitoring inflammation in reptiles. Several readily available diagnostic tests such as erythrocyte sedimentation rate (ESR), lactate, fibrinogen, and plasma protein electrophoresis (EPH) can provide insight into inflammatory disease in a multitude of species.^1-4 These tests are nonspecific in that they detect changes caused by inflammation of any etiology, but provide useful information about the presence of systemic inflammation. To the author’s knowledge, none of these analytes have been extensively evaluated in terrestrial chelonians. The objective of this study was to investigate the diagnostic performance of readily available inflammatory markers in the gopher tortoise (Gopherus polyphemus). In total, n=24 healthy and n=38 sick animals met the inclusion criteria. Reference ranges for healthy tortoises were established for ESR, lactate, fibrinogen by heat precipitation, EPH, and hematology. Receiver operating characteristic analysis revealed that the highest performing diagnostic tests were ESR (AUC=0.812; 95% CI=0.693–0.900), absolute heterophils (AUC=0.771; 95% CI=0.646–0.869), WBC estimate (AUC=0.767; 95% CI=0.642–0.866), and lactate (AUC=0.766; 95% CI=0.641–0.864). These results provide additional tools for the diagnosis and monitoring of inflammatory disease in gopher tortoises. Clinicians may consider adding ESR and lactate to the minimum database for this species.

Acknowledgments

The authors would like to thank Dr. Marjorie Bercier, Dr. Kyle Donnelly, Hollie Chiles, Cindy Coalter, and Justin Allen for their contributions to the animals cared for at the University of Florida Zoological Medicine Service. Additionally, Kathy Russell and the students/staff at Santa Fe College Teaching Zoo are recognized for providing long-term care to the healthy tortoises used in this study.

Literature Cited

1.  Bossart GD, Reidarson TH, Dierauf LA, Duffield DA. Clinical pathology. In: Dierauf LA, Gulland FMD, eds. CRC Handbook of Marine Mammal Medicine. Boca Raton, FL: CRC Press; 2001:422.

2.  Cray C. Biomarkers of inflammation in exotic pets. J Exot Pet Med. 2013;22:245–250.

3.  Lewbart GA, Hirschfeld M, Denkinger J, Vasco K, Guevara N, García J, Muñoz, Lohmann KJ. Blood gases, biochemistry, and hematology of Galapagos green turtles (Chelonia mydas). PLoS One. 2014;9(5):e96487.

4.  Parkinson L, Olea-Popelka F, Klaphake E, Dadone L, Johnston M. Establishment of a fibrinogen reference interval in ornate box turtles (Terrapene ornata ornata). J Zoo Wildl Med. 2016;47:754–759.

5.  Stacy NI, Alleman AR, Sayler KA. Diagnostic hematology of reptiles. Clin Lab Med. 2011;31:87–108.

6.  Sykes J, Klaphake E. Reptile hematology. Vet Clin North Am Exot Anim Pract. 2015;18:63–82.