Effects of lithium heparin and tripotassium EDTA on hematologic values of Hermann's tortoises (Testudo hermanni).

In an effort to define the effect(s) of lithium heparin and tripotassium EDTA on various hematologic parameters in Testudo hermanni, we collected blood samples from 29 clinically healthy adult individuals of both sexes. Portions of each blood sample were transferred to tubes containing either lithium heparin or tripotassium EDTA. The following determinations were made on samples of blood from each anticoagulant: red and white cell counts, packed cell volume, hemoglobin concentration, red cell indices, and differential white cell counts. Due to hemolysis, hematocrits could not be determined from blood samples in EDTA. Further, red blood cell counts were lower in the EDTA samples than in the heparin samples, again due to hemolysis associated with EDTA. However, EDTA did not appear to interfere with hemoglobin determinations. Heparin blood samples provided more optimal blood smears than did EDTA samples, thus differential leucocyte counts were determined only from smears taken from heparin blood samples. Further, thrombocyte and leucocyte aggregation was not observed with heparin use. Thus, heparin is considered the anticoagulant of choice in chelonians for determining red blood cell counts, erythrocyte indices, and hematocrits. When May-Grunwald-Giemsa stain was compared with Diff-Quick, thrombocytes could be more easily differentiated from lymphocytes using the May-Brunwald-Giemsa stain. Heterophil granules seemed to coalese more when Diff-Quick was used. Eosinophils, basophils, and monocytes were similar in appearance with both staining methods.