The Effects of Anticoagulant Choice and Sample Processing Time on Hematologic Values of Juvenile Whooping Cranes

Blood collected from juvenile whooping cranes (Grus americana) in 2007 and 2008 was divided and placed in either the anticoagulant lithium heparin (LiHep) or tri-potassium ethylenediaminetetraacetic acid (K3EDTA) for diagnostic hematology. Thin smears were prepared from the anticoagulated blood in the field with no delay and in the laboratory after a 4-6-hour delay, and then used to determine differential and total leukocyte counts. Manual heterophil and eosinophil counts were greater in LiHep-treated samples compared to K3EDTA samples (P < 0.05), but there was no difference in the total leukocyte concentration or differential leukocyte counts between anticoagulants based on blood smears prepared with no delay (n = 15). Marked differences were noted in relative heterophil (P < 0.05) and lymphocyte (P < 0.05) counts and total leukocyte (P < 0.05) concentrations of K3EDTA-treated samples processed after the delay (n = 7), suggesting a negative effect on lymphocyte integrity from the anticoagulant. Microscopically, lymphocytes were more intact and easily differentiated from thrombocytes in LiHep-treated samples than K3EDTA, but modest thrombocyte clumping in the LiHep samples was a concern. Either anticoagulant appears adequate for diagnostic hematology in juvenile whooping cranes based on this limited analysis, but blood smears should be prepared immediately under controlled conditions for best results. PROCEEDINGS OF THE NORTH AMERICAN CRANE WORKSHOP 11:105-109