Oxygen consumption and enzyme activity of the subtidal flat oyster (Ostrea chilensis) and intertidal Pacific oyster (Crassostrea gigas): Responses to temperature and starvation

Abstract

Intertidal Pacific oysters (Crassostrea gigas) and subtidal flat oysters (Ostrea chilensis) were held at 10, 15, or 20°C without food for 16 weeks. Rates of oxygen consumption in the subtidal oyster were more sensitive to temperature than those of the intertidal oyster, but temperature sensitivity decreased in starved Pacific oysters. Metabolic fuel reserves of glycogen in the adductor muscle were markedly higher in C. gigas, and decreased with starvation. Higher activities of the key metabolic enzymes, strombine dehydrogenase, alanopine dehydrogenase, and citrate synthase were found in C. gigas than in O. chilensis, indicating greater scope for energy production. These observations were consistent with the greater aerobic scope and glycolytic potential of C. gigas in the thermally variable intertidal environment, and in the face of severe nutritional challenge. Ostrea chilensis was metabolically challenged by warm temperatures and food deprivation, factors that need to be considered in the development of aquaculture methods for this species.

Key words:

• oyster
• respiration
• enzyme activity
• temperature
• nutrition