Effect of deltamethrin on haematological indices of common carp (Cyprinus carpio L.)

Abstract

The aim of this study was to assess the effect of deltamethrin [(S)- a -cyano-3-phenoxybenzyl (1R,3R)-3-(2,2-dibromvinyl)-2,2-dimethylcyclo-propancarboxylate] on common carp (Cyprinus carpio L.). The effect was assessed on the basis of the results of acute toxicity tests and on the comparison of results of haematological examination of a control and an experimental group exposed to Decis flow 2.5 pesticide preparation (active substance 25 g.l-1 of deltamethrin). The acute semistatical toxicity test lasting 96 h was performed on common carp juveniles. The 96hLC50 value of Decis flow 2.5 was 0.058 mg.l-1. Examination of erythrocyte and leukocyte profile was performed on 15 control and 28 experimental specimens of one-to-two-year-old common carp after 96 h of exposure to Decis flow 2.5 in a concentration of 0.13 mg.l-1. The experimental group showed significantly lower values (p < 0.01) of erythrocyte count (RBC), haemoglobin content (Hb), haematocrit (PCV) and plasma total protein (TP) compared to the control group. Values of MCV, MCH and MCHC were comparable in the two groups during the study. Also, the leukocyte count (Leuko) and relative and absolute count of lymphocytes, monocytes, neutrophil granulocytes and their developmental forms were comparable in the two groups. The deltamethrin-based Decis flow 2.5 pesticide preparation was classified among substances strongly toxic for fish. Changes in the erythrocyte profile and plasma total protein after exposure to deltamethrin-based preparation may be referred to possible disruption of haematopoiesis and proteosynthesis.