GROWTH AND SURVIVAL OF BLACKLIP PEARL OYSTER LARVAE FED DIFFERENT DENSITIES OF MICROALGAE
M.S. Doroudi, P.C. Southgate, R.J. Mayer-1999
Aquaculture International, 7 (3): 179-187
Abstract:
This paper reports on an experiment to determine growth and survival of blacklip pearl oyster, Pinctada margaritifera (L.), larvae fed a 1:1 mixture of Isochrysis aff. galbana clone T-ISO and Pavlova salina at six different densities (1, 2, 5, 10, 20 and 30 x 10^3 cells/ml). Larval growth and survival were assessed every 4 days over a 20 day period. Exponential and logistic regression models were fitted to the growth and survival responses, respectively. Overall growth of larvae fed >/= 5 x 10^3 cells/ml was significantly greater (p<0.01) than growth of larvae reared at other algal densities. The optimal food ration for maximum larval growth was 20 x 10^3 cells/ml, which resulted in larvae with antero-posterior shell length of 230 µm after 20 days. These larvae were significantly larger (p<0.05) than those in all other treatments at the end of the experiment. Survival of larvae fed 0, 1 and 2 x 10^3 cells/ml was significantly lower than that of larvae in all other treatments at the end of 15 days (p<0.01). Maximal survival (8%) over the 20 day period was shown by larvae fed 10 x 10^3 cells/ml, while lower survival was shown by larvae fed 2 x 10^3 cells/ml (2%) and 1 x 10^3 cells/ml (0%)
(Aquaculture Department, James Cook University, Townsville, Queensland 4811, Australia, e-mail: Mehdi.SavehDoroudi@jcu.edu.au)