Abstract

Healthy reptiles possess significant variation in clinical pathology values based on age, sex, season, and reproductive state. Traditional methods used to assess health, such as complete blood counts and biochemistries are often not rewarding in determining disease status. Erythrocyte sedimentation rate (ESR) is an indirect, inexpensive, tabletop analytical method to screen for inflammatory disease in numerous species, including humans and cetaceans. Greater ESR values are often associated with disease. In reptiles, ESR has been evaluated in two species, the gopher tortoise (Gopherus polyphemus) and the North American box turtle (Terrapene spp.).^1,2 The objective of this observational study was two-fold: ESR was evaluated throughout the rehabilitation process for cold stunned Kemp’s ridley sea turtles (Lepidochelys kempii) and agreement was assessed between two methods to determine ESR. Twenty-five rehabilitating L. kempii were enrolled in the observational study to compare two methods of erythrocyte sedimentation rate. Blood was collected 4–7 days post stranding, upon transfer, and intake. Samples were processed within 5 minutes of collection. Heparinized blood was used to perform ESRs via two methods: a commercial kit (Sedi-Rate™) and non-heparinized microhematocrit tubes. ESRs from both the Sedi-Rate™ and microhematocrit methods were analyzed for agreement using Bland-Altman plots.³ Passing-Bablok regression was utilized to determine whether there were systematic or proportional errors between the two methods.⁴ Upon animal intake, mean ESR using Sedi-Rate™ method was 7.5 mm (SD: 2.06 mm; min–max: 4–14 mm). Mean ESR using the microhematocrit method was 5.65 mm (SD: 1.84 mm; min–max: 2.18–8.95 mm). Recheck examination 23 days following admission showed a significant (p=0.001) increase in mean ESR using the Sedi-Rate™ method (9.75 mm; SD: 2.64 mm; min–max: 4–16 mm) and a significant (p=0.011) increase in mean ESR using the microhematocrit method (8.09 mm; SD: 3.29 mm; min–max: 3.83–15.66 mm). Initial analysis demonstrates there may be systematic differences in the methods but no proportional differences between the two methods to date. Erythrocyte sedimentation rate performed with either method could be a rapid screening tool for disease in L. kempii.

*Presenting author

Literature Cited

1.  Adamovicz L, Baker SJ, Kessler E, Kelly M, Johnson S, et al. 2020. Erythrocyte sedimentation rate and hemoglobin-binding protein in free-living box turtles (Terrapene spp.). PLoS One 15(6):e0234805.

2.  Rosenberg JF, Hernandez JA, Wellehan JFX, Crevasse SE, Cray C, Stacy NI. 2018. Diagnostic performance of inflammatory markers in gopher tortoises (Gopherus polyphemus). J Zoo Wildl Med 49:765–769.

3.  Bland JM, Altman DG. 1986. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1(8476):307–310.

4.  Passing H, Bablok W. 1983. A new biometrical procedure for testing the equality of measurements from two different analytical methods. Application of linear regression procedures for method comparison studies in clinical chemistry, part I. J Clin Chem Clin Biochem 21(11):709–720.