Validation of the HemoCue® WBC System as a Point-of-Care Device for Bottlenose Dolphins (Tursiops truncatus) and Determination of Variables that Interfere with Results
Abstract
Total white blood cell (WBC) count is commonly used to assess health and is frequently calculated via an automated analyzer, typically off-site in central laboratories, delaying results. The HemoCue® WBC System portable analyzer delivers results within 3 minutes, and studies in humans have shown agreement between the HemoCue® and reference methods.1-3 Our objective was to validate the HemoCue® as a diagnostic tool for total WBC count in bottlenose dolphins (Tursiops truncatus) and determine variables that interfere with the HemoCue® (i.e., hematocrit, nucleated red blood cells (nRBC), and platelet count). We hypothesized the HemoCue® would not be significantly different from the reference laboratory (Balboa Naval Medical Center San Diego [NMCSD]) or manual estimated WBC count; and low hematocrit, increased nRBC, or thrombocytosis would cause inaccurate HemoCue® results. Sixty-five blood samples from dolphins at the U.S. Navy Marine Mammal Program (San Diego, CA) were collected during routine health care. Manual estimated WBC count, HemoCue®, and complete blood count from NMCSD were analyzed. Platelet count and nRBC count were analyzed at NMCSD; hematocrit was performed in-house. Analysis showed no significant difference between the HemoCue® WBC, NMCSD WBC, and manual estimated WBC count (p<0.05). Platelet count and hematocrit did not interfere with HemoCue® results; however, the presence of nRBC significantly affected the difference between HemoCue® and NMCSD WBC results (p<0.05). This suggests the HemoCue® WBC is a reliable tool to measure the total WBC count and is useful when immediate results are indicated or a reference laboratory is not available.
Acknowledgements
The authors wish to thank the National Marine Mammal Foundation and the U.S. Navy Marine Mammal Program for their contributions to this study and their efforts in advancing clinical diagnostics for bottlenose dolphins.
*Presenting author
Literature Cited
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