Effets de l'exposition à un insecticide carbamate, le carbofuran, sur les performances de jeunes stades de brochet (Esox lucius L., 1758) : résultats préliminaires

Abstract

Pike free embryos were introduced into glass beakers and exposed under static conditions to solutions (0-250 ug.L 1 ) of carbofuran, a carbamate insecticide inhibiting acetylcholinesterase (AchE) activity. From a carbofuran concentration of 10 ug.L 1 , the overall AchE activity in free embryos was significantly inhibited. From 50 ug.L 1 , the mean -530 -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 ug.L' 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.

Temporal changes in vertical distribution, body orientation and mobility of pike (Esox luciusL.) free embryos: Individual observations under controlled conditions

“…All the other phases (1, 2, 4, 5) were characterized by much higher levels of variability, particularly among individuals: after hatching, the embryo gains the capability to move freely from place to place and to experience changes in body orientation; a truly individual behaviour can then be expressed, with increased variability as a potential consequence. The mean height of attachment of pike free embryos has been used as a biological indicator of insecticide neurotoxic effects (Amblard et al, 1998). The results of the present study strongly suggest, in an ecotoxicological context, to select the plateau phase (days 5-8 at 10…”

“…Studying spatial distribution appeared as fully justified from an ecological standpoint, since the position of a free embryo in the water column will contribute to determine exposure to environmental conditions and might ultimately influence growth and survival (Chambers and Trippel, 1997). As the mean level of attachment of free embryos has been proposed as a tool to measure ecotoxicological responses (Amblard et al, 1998), a particular attention was paid to the maximum levels attained in the water column during attachment behaviour. Previous works dealt with observations on groups of free embryos; in contrast, we felt that individual-centered observations would provide a more precise insight into the studied biological phenomenons.…”

Effects of Carbofuran, Diuron, and Nicosulfuron on Acetylcholinesterase Activity in Goldfish (Carassius auratus)

“…A slight di!erence in the temperature of exposure used in the two studies might partly account for such discrepancy (Habig and Di Giulio, 1991;Zinkl et al, 1991). Conversely, Amblard et al (1998) have found that the e!ect of exposure to carbofuran on mean height of attachment of pike embryos was produced by a higher concentration (50 g/L) than the one inhibiting AChE activity (10 g/L). In channel cat"sh, Carter (1971) correlated behavioral signs of acute poisoning by several carbamates with brain AChE inhibition.…”