Postmortem vitreous chemistry in common bottlenose dolphins: a precision and stability study

Background Postmortem vitreous chemistry is an understudied analytical test in marine mammals.Methods We assessed the analytical precision of pooled common bottlenose dolphin vitreous humor (VH) samples using the Heska Corporation Element DC chemistry analyzer and to examine the short-term stability of pooled VH when stored at room temperature and in a hot environment (inside a vehicle).Results The within-run and between-run CVs for all detectable analytes were <20%, with most <5%, indicating acceptable repeatability within the pooled matrix. At room temperature, Ca and Mg had statistically significant decreases over the 4-hour period, and in the hot vehicle condition, Ca had a statistically significant decrease over the same period. Potassium and glucose concentrations were outside the instrument's reportable range, representing a limitation for postmortem interpretation.Conclusion These results from this proof-of-concept feasibility study demonstrate that the Element DC chemistry analyzer can produce repeatable measurements in a pooled dolphin VH matrix. Further studies are required to evaluate the applicability of this platform including analytical accuracy, matrix effects, or performance in individual postmortem samples under real-world conditions.