Attached
Experiments were conducted to identify suitable
methods for broodstock rearing, induced breeding
and grow-out culture of Holothuria scabra in Sri
Lanka. Two hundred and seventy-two brooders
(500–600 g) collected from off Mannar were individually packed in oxygen-filled polythene bags
with and without sea water and transported to a
sea cucumber hatchery at Kalpitiya. Lagoon pens,
sand-filled fibreglass tanks and bare tanks were
used in triplicates to maintain brooders. Spawning
was initiated using air dry, water jet and thermalstimulation methods. Hatchery produced juveniles
with an average weight of 11 5 g were reared (2
individuals m2
) in lagoon pens, mud ponds and
fibreglass tanks in triplicates. The significantly high
evisceration rate was observed when brooders were
transported without sea water (t-test, P < 0.05).
Brooders maintained in bare tanks showed a significant weight reduction than the brooders in sandfilled tanks and lagoon pens (ANOVA, P < 0.05,
d.f. = 2). Thermal stimulation (ambient temperature 3–5°C) was found to be the most successful
method of spawning initiation of H. scabra. The
mean ( SD) percentage males and females participated for spawning per trial was 9.2 ( 10) and 4.6
( 5.6) respectively. On an average, 1.16 millions of
eggs ( 1.03 SD, n = 5) were obtained per spawning
trial. H. scabra juveniles reared in tanks showed significantly lower growth rate than the juveniles in
pens and ponds (ANOVA, P < 0.05). Lagoon pens and
sand-filled tanks are suitable to maintain brooders
and lagoon pens can be successfully used for mass
rearing of juveniles.
