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 PARENT SESSION
3D - Exposure and effects of environmental contaminants in marine organisms
Poster Hall
8:30 AM - Tuesday, 29 April 2003
Chair: Scholz, N.1, 1
Co-chair: Karbe, L.2, 2
(TUP/188) The effects of a triazole-derivative fungicide to the marine shrimp post-larvae Litopenaeus vannamei.
Roussel, Helene1, Betancourt-Lozano, Miguel2, Baird, Donald1, 1 Institute of Aquaculture, Stirling, Scotland2 CIAD, Mazatlan, Mexico
ABSTRACT- Toxicity of a triazole-derivative fungicide to Litopenaeu vannamei post larvae was examined, by studying feeding, moulting, morphology and behaviour as sub-lethal endpoints to toxic stress. Two fungicides were tested: TILT 250E (commercial formulation which is containing 25% propiconazole) and technical grade propiconazole (92,4% purity). Short-term toxicity test (96h) were performed on post larvae exposed to different concentrations of toxicants in a static system with daily water-renewal. The LC50 (96h) was 673  g/L for TILT (concentration based on active compound content) and 1256 g/L for propiconazole. Since mortality endpoints have limited ecological significance, sub lethal concentrations of 80, 155 and 300 g/L were taken to evaluate effects on feeding, moulting, morphology and behaviour. Results showed that feeding rate was negatively affected by all the concentrations of TILT (80, 155 and 300/l) and slightly increased by the highest concentration of propiconazole (300/L). Intermoult duration was increased by two concentrations of TILT (155 and 300g/L) and decreased by two concentrations of propiconazole (155 and 300 /L). Further experiments revealed that TILT and propiconazole at sub lethal doses were not producing morphological deformities but were inducing abnormal behaviour in Litopenaeus vannamei post larvae. The possibility to use the post larvae Litopenaeus vannamei as standard species for marine chronic toxicity tests was examined with those findings, showing a practicable, cost effective reproducible and relevant toxicity test.
Key words: propiconazole, Litopeneaus vannamei, TILT250E, sub lethal tests
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