Effect of copper exposure on growth, condition indices and biomarker response in juvenile sole Solea senegalensis

摘要

Juvenile Solea senegalensis were exposed to different concentrations of waterborne copper (Cu) for 15 days ill static conditions with continuous aerated artificial salt water at 20 degrees C (+/- 0.8 degrees C with a normal photoperiod (10 h/14 h light/dark) and daily feeding. Several measures of exposure and effects were determined: 1) biomarkers - metallothioneins and lipid peroxidation level; 2) mass indices - growth rate and morphometric condition indices; and 3) biochemical condition indices - RNA:DNA ratio and lipid and protein content in fish tissues. Copper exposure triggered the response of the biomarkers and resulted in reduced growth and condition (RNA:DNA and lipid content), but the morphometric indices did not vary. The physiological costs of Cu contamination on condition Suggested that lipid reserves were allocated as an energy Source to enable exposed fish to respond to Cu toxicity as well as to maintain positive growth rates and protein synthesis throughout the experiment, although with lower growth rates than the control fish. This study showed the importance of selecting suitable biomarkers according to contaminant source, fish Species and their life-history stage. In addition, the use of several biomarkers of exposure, growth and specific condition indices call improve fish health determination and should be considered in evaluations of the effects of environmental contaminants on fish.