Effects of carbofuran, a carbamate insecticide, on biological performances of young pike (Esox lucius L., 1758):: Preliminary results.

Pike free embryos were introduced into glass beakers and exposed under static conditions to solutions (0-250 mu g.L-1) of carbofuran, a carbamate insecticide inhibiting acetylcholinesterase (AchE) activity. From a carbofuran concentration of 10 mu g.L-1,,the overall AchE activity in free embryos was significantly inhibited. From 50 mu g.L-1, the mean level of attachment of free embryos to the beakers walls decreased significantly. The number of zooplanktonic prey ingested by pike larvae was not significantly affected by exposure to carbofuran; however, this parameter tended to decrease with increasing concentrations of carbofuran. In free embryos exposed to 250 mu g.L-1 carbofuran, yolk sac resorption was very incomplete and the transformation into larvae did not take place. The present study demonstrates that sublethal exposures to carbofuran may affect ontogenetic changes and biological performances in pike young stages. Further developments of this work are planned in several directions.