4.5. Conclusion
There was an accumulation of lipid reserves during larval development
of S. verreauxi and a significant increase in lipid utilisation beyond
instar 17, characterised by a decrease in the C:N ratio. This is due to the
depletion of lipid as an energy reserve to fuel metamorphosis and the
non-feeding puerulus stage. Independent measurements of N and protein
also found protein values were considerably lower than crude protein
values calculated from the theoretical factor of 6.25, suggesting
that a conversion factor of 6.25 was too high. This may be due to considerable
amounts of N being present in chitin and free amino acids in
phyllosoma. Although there were no significant differences in the protein
content of phyllosoma cultured at LD and HD, the lipid content, C:N ratio,
growth and development of phyllosoma was negatively affected in the
HD treatment possibly because of reduced feeding success and increased
energy expenditure. Therefore, larval culture requires careful examination
of stocking densities to prevent situations of reduced phyllosoma
condition and growth.