OPTIMAL STAINING OF LIPIDS IN BIVALVE LARVAE WITH NILE RED

A procedure to stain oyster larvae Crassostrea virginica with the fluo rescent, lipid-specific dye Nile Red was developed. Experiments were p erformed to select for optimal carrier solvent, staining time, stain c oncentration, fixation regime and time of observation under the fluore scence microscope. The technique allows relative quantification of lip ids in individual larvae. The optimal staining technique was: Nile Red dissolved in acetone applied on live larvae (unfixed and starved for 6 h prior to staining), at a concentration of 1.25 mug/ml, staining fo r 1.5 h, and fluorescence measurements within 4 h after staining. Up t o 1000 larvae can be analysed per day.