Hematology-instruments that analyze blood cells can at specific cases be followed by manual counting with a Hemocytometer. The plastic Hemocytometer which has a fixed coverslip and is assigned for disposable use, appears to reduce the problems arising from the use of the traditional glass Hemocytometer, for instance coverslip-application difficulty and dust particles. Capillary whole blood sampling may be useful for patients at the emergency department and in addition, a smaller volume of blood is taken compared to venous blood sampling. This study will focus on the platelet- and leukocyte count (PLT and WBC) in venous and capillary blood, in order to compare the plastic- and glass Hemocytometers with Sysmex XN-2000 (Sysmex Corporation, Kobe, Japan), and verify if capillary whole blood sampling can be used for the measurement of these hematological parameters. 30 subjects donated both capillary- and venous blood samples and these blood samples were analyzed with glass- and plastic Hemocytometers with Sysmex XN-2000 as the reference method.

Platelet aggregation is a major and common problem in blood samples from cats. This greatly affects the accuracy of counting of the platelets. Because of the difficulties in counting feline platelets, results for patients and reliable reference values for cat platelets are currently so inaccurate as to be almost useless in diagnosis of thrombocytopenia. In this study we used an effective method to prevent platelet aggregation. Blood was collected in CTAD test tubes and prostaglandin E1 was added to the blood sample.