Aims: Heparin and EDTA salts are commonly used as anticoagulants for haematological studies in fish. This study aimed at investigating the effect of heparin and Ethylenediaminetetraacetic dihydrate (Na₂EDTA) on some haematological parameters of Sterlet sturgeon (Acipenser ruthenus). Materials and Methods: In the current experimental study, the effect of heparin (10ml) and N_a2EDTA (1mg/ml) was investigated on haematological parameters in Acipenser ruthenus. The blood samples were collected from 10 healthy fish with the average weight of 600.0±63.0g. The data were analyzed by SPSS 22 software, using one-way analysis of variance, independent t test, and Duncan's new multiple range test.
Findings: The number of red blood cells in samples containing N_a2EDTA (845000±123532cell/mm³) was significantly lower than those of heparinized ones (1205000±86270; p<0.05). Mean haematocrit value for N_a2EDTA samples (27.05%±0.46) was significantly higher than bloods preserved in heparin (23.62%±0.89%; p<0.05). In sample containing N_a2EDTA, mean corpuscular volume (MCV) and lymphocyte (149.11±30.00ft and 93.25±1.55%, respectively) was significantly higher than the heparin sample (108.59±18.41ft and 87.25±1.72%, respectively; p<0.05). In sample containing N_a2EDTA, the increase in size and haemolysis of red blood cells were observed, but the changes in the sample containing heparin did not differ significantly from that of the control group.
Conclusion: Na2EDTA has a negative effect on haematological parameters of Acipenser ruthenus, especially in morphological terms; so, it is not a suitable anticoagulant combination for blood analysis of this species. Heparin due to the smallest changes in shape and size of cell, as well as less effect on hematocrit, is an anticoagulant in sterilized fish haematological studies.