Effects of time of collection and sample processing on von Willebrand factor concentration in retired racing greyhounds

Background: Concentrations of von Willebrand factor (vWF) are less than 30% in approximately 10% of Greyhounds. Hypothesis: That sample collection, processing, and storage can affect the concentration of vWF in plasma of Greyhounds. Animals: Nineteen healthy former racing Greyhounds. Methods: Prospective study: Blood samples were obtained from the jugular vein of dogs at 4 times during the day. Samples were divided and processed in each of 3 ways. The 1st tube was centrifuged immediately, the 2nd tube was kept in a household refrigerator, and the 3rd tube was kept at room temperature for 3 hours before centrifugation and processing. Results: There were no significant differences in the vWF concentration between different sample storage and processing (P=5.31). There was no statistically significant diurnal variation in vWF concentration in the samples evaluated (P=.37). Conclusions and Clinical Importance: Time of sample collection and short‐term storage temperature do not influence the vWF concentration in retired racing Greyhounds.