Author(s): Thirunavukkarasu. N, Sheeba Anitha Nesakumari. C, A. Shanmugam. A

Abstract: The larval rearing and seed production experiment, the berried S. tranquebarica transferred to 1 ton tank filled with clean filtered and aerated seawater and 0.1 ppm Treflan (44% trifuralin) every three days in the hatching tanks. Salinity was maintained at 35 ppt, pH 7.8-8.2 and temperature 30-32.5 0C. Everyday larvae were counted for check the survival. The rearing water replaced at 20% daily after 5 days of stocking of larvae. Feeding starts after 3 hours of hatching of the larvae. Feeding schedule zoeae I was fed with Brachionus rotundiformis twice per day morning and evening (ad libitum). The zoeae II to IV were fed with B. rotundiformis and the enriched Artemia nauplii (2 times). Zoeae V and megalopa were fed with the enriched Artemia nauplii and the formulated feed respectively (2 times). The period of incubation noted and it was 12 days. The complete larval development of S. tranquebarica consists of five zoeal and one megalopal stages before moulting into crab instar stage. The zoeal stages (I to V) required the minimum time of 4,3,3,3 and 3 days respectively, megalopa required 6 days to metamorphose into crab instar stage. The complete larval development was took place within a span of 22 days. The survival of the first zoeae to crab instar stage was 6.9%.



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