Effects of Exposure to a Glyphosate-Based Herbicide on Haematological Parameters, Plasma Biochemical Indices and the Microstructure of Selected Organs of the Common Carp ( Cyprinus carpio Linnaeus, 1758)

Contamination of water environments with herbicides is a common problem nowadays. The aim of the current study was to evaluate the effects of Roundup on common carp ( Cyprinus carpio) after 1, 3 and 10 days of exposure. The used concentrations corresponded to 1 and 5 mg/l of
 the active ingredient (glyphosate potassium salt). The haematological analysis performed showed a decrease of the RBC count, as well as an increase of the other erythrocyte indices (Hb, MCV, MCH, MCHC). Most of these changes were dependent on the concentration and time. An increase of the
 WBC count and the percentage of immature neutrophils occurred, thus indicating the presence of inflammation. In the studied blood biochemical parameters, only minor and temporary changes were observed. The histopathological analysis revealed no alterations in the gills, liver and kidney. Thus,
 the results of the present study suggest that the haematological parameters are more sensitive and reliable markers of the common carp's exposure to Roundup than the other parameters that were tested.