Assessment of the hemorheological profile of koala and echidna
Oguz K. Baskurt a,*, Sonya Marshall-Gradisnik b, Michael Pyne c, Michael Simmonds d, Ekua Brenu b, Rhys Christy b, Herbert J. Meiselman e
a Department of Physiology, Faculty of Medicine, Akdeniz University, Dumlupinar Blv., Antalya 07058, Turkey
b Faculty of Health Sciences and Medicine, Bond University, Robina, Queensland 4229, Australia
c Currumbin Wildlife Sanctuary, 28 Tomewin Street, Currumbin, Queensland 4223, Australia
d School of Physiotherapy and Exercise Science, Gold Coast Campus, Griffith University, Queensland 4222, Australia
e Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Health Sciences Campus, Los Angeles, CA 90033, USA
Koala, a marsupial, and echidna, a monotreme, are mammals native to Australia. Blood viscosity (62.5–1250-1), red blood cell (RBC) deformability, RBC aggregation, aggregability and surface charge, and hematological parameters were measured in blood samples from six koalas and six echidnas and compared to adult human blood. Koala had the largest RBC mean cell volume (107.7 ± 72.6 fl) compared to echidna (81.3 ± 72.6 fl) and humans (88.4 ± 71.2 fl). Echidna blood exhibited the highest viscosity over the entire range of shear rates. Echidna RBC were significantly less deformable than koala RBC but more deformable than human RBC. Echidna RBC had significantly lower aggregability (i.e., aggregation in standardized dextran medium) than koala or human RBC, while aggregation in autologous plasma was similar for the three species. Erythrocyte surface charge as indexed by RBC electrophoretic mobility was similar for human and echidna cells but was 40% lower for koala RBC. Data obtained during this preliminary study indicate that koala and echidna have distinct hemorheological characteristics; investigation of these properties may reveal patterns relevant to specific behavioral and physiological features of these animals.