Reproductive performance and
offspring quality in mud crab (Scylla paramamosain) broodstock fed
different diets
I.S. Djunaidah, M. Wille, E.K. Kontara, P. Sorgeloos-2003
Aquaculture
International, 11
(1-2): 3-15
Abstract :
A 2-month feeding trial was conducted to evaluate the
reproductive performance and offspring quality of mud crab (Scylla
paramamosain) females fed either a mixture of fresh food items (squid,
shrimp, trash fish and Artemia biomass) or two experimental diets
developed for penaeids. Before test initiation, mud crab females with an
average individual wet weight of 200–300 g
were acclimated for 2–3 days and reared
together in one concrete tank of 2.0 × 0.5 ×
8 m until spawning. After spawning, the spent spawners were unilaterally
eyestalk ablated and randomly divided (20 animals/treatment) over three
tanks of the same size and subjected to the dietary treatments. Spent
spawners were used to eliminate the effect of feeding history.
There were only minor differences in reproductive
performance between dietary treatments. No differences were observed in the
duration of the latency period from eyestalk ablation to spawning. Fecundity
was only marginally higher for the broodstock fed the control diet. Also egg
quality seemed only slightly affected by the treatments. Egg hatching rates
were slightly higher in crabs fed the formulated diets compared to those
crabs fed the fresh diet. The only statistically significant difference (p
< 0.05) observed however was in egg hatching rate between the control
diet and diet A2. In contrast, the crabs fed the fresh diet produced
stronger larvae as determined by a starvation test.
We therefore conclude that artificial diets resulted
in reproduction success comparable to the use of fresh food. The nutritional
composition of the artificial diets could however be improved in order to
produce larvae of optimal quality. Based on our research findings, the
protein level and n-3 HUFA level in the diet warrants further investigation
in this respect.
(Center for
Brackishwater Aquaculture Development, Jalan Pemandian Kartini, PO Box 1,
Jepara, Indonesia, e-mail of P. Sorgeloos: patrick.sorgeloos@Ugent.be)