Comportement de Crassostrea Angulata lamarck sous des conditions d'asphyxie

The oyster's ability to survive in the absence of oxygen is well known. The only means of defence that these sedentary organisms have for fighting against unfavourable environmental conditions or predators is occlusion of the valves. This implies anaerobiosis potential. This way of life occurs frequently: in the oyster beds, following the most violent storms, the oysters are piled up or covered with sand; they survive in this situation for several days until the oyster farmers put them back to take advantage of the spring tides that enable the drying out of the breeding areas; during periods when the runoff basins are overloaded, the dissolved oxygen content of the sea water are very low and significant mortality rates are sometimes observed in the submerged oysters. The main subject of our research was to determine Crassostrea angulata LMK's survival time following the progressive consumption of the available oxygen and the accumulation of metabolic waste. A secondary interest arose. Indeed, for a few years now, oysters have been infected by "gill disease" and the deficient physiological state of the most affected subjects diminishes their ability to resist. We tried to clarify this influence.