Comparative Effects of Microalgal Species on Growth, Feeding, and Metabolism of Pearl Oysters, Pinctada fucata martensii and Pinctada maxima

Pinctada fucata martensii and P. maxima are two main traditional pearl oyster species that can produce seawater pearls. Our previous study showed a higher clearance rate (CR) growth performance in f. than fed with Isochrysis galbana . In this study, the juveniles of sizes (large small) were six different microalgae diets [ I. ( I ), Platymonas subcordiformis P Chaetoceros muelleri I, I+P, I+C, P+C] to evaluate differences growth, feeding, metabolism between species. After 60 d rearing period, mixed significantly relative (RGR) those single (P< 0.05). The RGRs same decreasing tendency both CRs oysters 0.05), Significantly lower respiration rates (RRs) observed small-size groups P, I+P all large compared Higher activities amylase, cellulase, lipase, pepsin at sizes. decreased while there no consistent growth. carbonic anhydrase highest I+C diet group, followed by C+P C, groups. Significant among results suggest CR digestive enzymes RRs may cause