The acute intoxication of Cypermethrin in Silver Catfish (Rhamdia quelen) was evaluated. Animals weighing 56.67±4.43g and measuring 18.92±1.16cm were exposed to sublethal concentrations of Cypermethrin for the species in hydrological conditions during 96 hours. A total of 52 fish divided into three groups were used and received the following concentrations of Cypermethrin: 0 (n=12); 1.5 (n=20) and 2.5 (n=20)mg/L. The intoxicated animals suffered behavioral changes such as loss of balance, swimming alteration, dyspnea, upright swimming and sudden spiral swimming movements. As soon as the 96-hour period was over, a blood collection for hematological and biochemical analyses was performed. A complete haemogram test, plasmatic protein test, albumin, alanine transaminase (ALT), aspartate aminotransferase (AST), gamma glutamyltransferase and alkaline phosphatase (ALP) were studied. The values of erythrocytes, hematocrits, haemoglobin, total number of leukocytes, thrombocyte, ALT, AST and ALP changed according to the groups. The results have shown that the environmental contamination by Cypermethrin is toxic to the species.
fish; biomarkers; ecotoxicology; haemogram; pyrethroids