GROWTH AND SURVIVAL OF SPISULA SOLIDISSIMA SIMILIS LARVAE FED DIFERENT RATIONS OF TAHITIAN STRAIN ISOCHRYSIS SPECIES

D.H. Hurley, R.L. Walker, F.X. O'Beirn-1997

Journal of Shellfish Research, 16(1):151-155

Abstract:

Laborator-spawned veliger-stage larvae of the southern Atlantic surfclam, Spisula solidissima similis (Say 1822), were reared to late pediveliger stage in five different cell concentrations of Tahitian strain Isochrysis species (T-Iso) to determine an optimal food ration for this subspecies. Larvae were fed daily 0, 50,000, 100,000, 200,000, or 300,000 cells/mL of T-Iso. Day-old veliger larvae were stocked in 150 (1-L) replicate flasks at mean densities of 0.7 or 0.8 larvae/mL for trials A and B, respectively. Larval growth and survival were assessed every 2 days over the 14-day trial periods. Significantly greater growth and survival of larvae occurred in both trials in the lower food rations of 50,000 and 100,000 cells/mL. A reduction in larval growth rate and survival was observed at the higher ration treatments. A decline in overall larval health may be associated with the deliterious effects of surplus ration degradation.

(Shellfish Aquaculture Lab, University of Georgia, Marine Extension Service, 20 Ocean Science Circle, Savannah, Georgia 31411-1011, USA)

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