ANAEROBIC METABOLISM IN THE SHRIMP CRANGON-CRANGON EXPOSED TO HYPOXIA, ANOXIA AND HYDROGEN-SULFIDE

The brown shrimp Crangon crangon was collected in the Penze estuary, Bretagne, in April 1994 and exposed to hypoxia, anoxia and combinations of hypoxia and sulfide. Exposure to sulfide induced total anaerobic metabolism even at an oxygen saturation which would otherwise permit totally aerobic metabolism. In addition to preventing aerobic metabolism there was a direct toxic effect of sulfide. Haemocyanin oxygen affinity (p(50)) values from non-stressed C. crangon were relatively low. The p(50) values all exceed those where environmentally induced lactate accumulation occurs. It seems unlikely that lactate is an affinity modulating factor under environmental hypoxia.