Biochemical changes in the Pacific oyster, Crassostrea gigas (Thunberg, 1795), during larval development and metamorphosis

Graduation date: 1979The energy strategies of early development of the Pacific Oyster,\ud Crassostrea gigas, were examined. Changes in proteins, total carbohydrates,\ud free reducing sugars and total and neutral lipids were\ud determined for the unfertilized egg and larval stages through 13 days\ud post-settlement.\ud During early larval stages neutral lipid levels decreased and\ud provided the principle source of energy for development. Subsequently\ud they remained unchanged throughout settlement and metamorphosis.\ud Protein levels increased during larval stages and remained\ud largely unchanged after settlement. Total carbohydrate levels were\ud unchanged during larval development and through settlement and metamorphosis.\ud Phospholipid values rose slightly during early larval\ud stages and remained unchanged through settlement and metamorphosis.\ud Starvation experiments confirmed the aforementioned findings\ud that neutral lipid was an important source of energy during early\ud larval life. Protein, however, contributed more energy than neutral\ud lipid in late larval life.\ud This study has shown that in C. gigas development, contrary to\ud the European oyster Ostrea edulis, neutral lipid was not accumulated\ud during larval feeding nor utilized during settlement and metamorphosis\ud relative to other organic fractions