Red sea bream eggs and larvae of several stages including; just after hatching, 16-day old, 37-day old, 49-day old and 80-day old were preserved in 3%, 5%, 10% neutral formalin to observe effects of the preservations on length and weight. The measurement of the length and weight were made on the same specimens of the each groups every 4 weeks during 6 months. Filtered sea water of about 32‰ salinity were used for solvent of the preservative.
Eggs increased initially in diameter while, the larvae of each stage decreased drastically during the first observation period then assumed stable form in size. Shrinkage decreased increasingly for both length and weight as the initial size of specimens increased specifically; a 16-17% decrease from the initial length was observed for the newly hatched larvae, but only about a 2% decrease in size was recorded for the fry of 80-day old.
Significant changes were not observed between initial and final egg diameters. No significant differences in degree of shrinkage at various ages were found among the concentrations of 3%, 5% and 10% formalin solutions.
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