Study Effects of Ethylenediaminetetraacetic Acid (EDTA) on Haematological Parameters in Onchorhynchus mykiss Juvenile

In this study acute toxicity (96h LC50) of EDTA has been carried out in laboratory conditions in 2011 fall for rainbow trout. The experiments were conducted for 96h with standard method (O.E.C.D). LC50 values of EDTA at 96 h were 2231 mgl-1, to the rainbow trout. Then, individuals with a body weight of 51 ± 12 g and length 18.5 ± 2.1 cm were selected for six groups (five test group and control group). Onchorhynchus mykiss were exposed to 800, 1100, 1400, 1700 and 2100 mgl-1 of EDTA. Fish were exposed for 96 h. The experiments periods were controlled water physicochemical factors such as: pH, total hardness, dissolved oxygen and temperature. For analysis of all data SPSS software program was used. Haematology results show that exposure to EDTA causes an increase in leukocyte count (WBC), neutrophil, eosinophil, monocyte and a decrease in haemoglobin (Hb), haematocrit (HCT) and lymphocyte (P<0.05). Also, there are no significant effects in erythrocyte count (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) (P>0.05). The results showed that exposure to low concentrations of EDTA causes changes in some haematological parameters of rainbow trout and may weaken the fish immune system. The results of this research showed that toxic EDTA endangers health of Onchorhynchus mykiss.