| dc.description.abstract | One of the problems in blue swimming crab seedling is the high rate of mortality. This study
is aimed at analyzing the influence of mulberry extract (ME) on the survival rate of crab
larvae which are managed to metamorphose to the next stage and on the rate of larval
development, as well as identifying various factors causing mortality in the mass cultured
larvae, mainly mortality caused by molting syndrome. There are 4 treatments of different
doses of mulberry extract being tested which are: 0 mg/100 g (control), 1 mg/100 g, 2 mg/100
g, and 4 mg/100 g. Mulberry extract is given through feeding since day-8 of the stocking,
which is the time when larvae enter zoea 3. The rearing process is done over 19 days in a
concrete tank with a volume of 1 ton with the initial number of zoea at ± 350.000. The
findings show that mulberry extract has a significant influence on the survival rate, stage
growth, and the mortality rate of blue swimming crab larvae due to molting syndrome. The
higher the dose of ME in the artificial food, the higher the survival rate and the lower the
mortality rate due to molting syndrome. The treatment with 4 mg of mulberry extract/100 mg
is the only treatment which successfully enters megaloph and crab stage. Control treatment
and the dose of 1 mg/100 g can only reach zoea 3 while the dose of 2 mg/100 g can only
reach zoea 4. This study shows that the total mortality rate is still high, but it is found that the
main cause is not molting syndrome. Mortality rate due to molting syndrome in the treatment
of the dose of 4 mg of mulberry extract is only ± 15.61% of the total larval mortality. The
unidentified factors dominate the cause of mortality (± 57.47%). Other factors are fungal
attack (±17.65%), morphological disorder (±9.28%), and cannibalism (±14.93%). | en_US |
