Seed production and juvenile
rearing of the tropical abalone Haliotis varia Linnaeus 1758
T.M. Najmudeen, A.C.C. Victor-2004
Aquaculture, 234(1-4): 277-292
Abstract:
Spawning, larval and juvenile rearing of the tropical
abalone Haliotis varia L. were studied. Brood stock abalone were
induced to spawn by exposure to air for 2 h at 27 °C. Female abalone
spawned a mean of 76,530 eggs. Fertilised eggs measured 180 µm in diameter.
Seventy percent survival was obtained during larval rearing. Larvae passed
trochophore, veliger, gliding and creeping stages and were induced to settle
on a mat of diatoms containing Nitszchia sp. and Navicula sp.
The larval rearing period of H. varia ranged from 4 to 6 days at 27
°C. The settled spat vigorously fed on the diatom mat until the 50th day of
postfertilisation and coralline red algal film, until the 70th day of
postfertilisation. First respiratory pore was formed on the 27th day of
postfertilisation. Juvenile abalones were reared on three algal diets such
as coralline red algae, green filamentous algae and Ulva lactuca from
the 71st to 200th day of postfertilisation. Those fed with coralline algae
showed best and consistent growth. Shell colour of juveniles was affected by
diet. The present study on the production of juveniles in the hatchery is a
baseline information to initiate abalone aquaculture in India and to help
augment the natural population.