Behaviour, tolerance and anaerobic metabolism under hypoxia in the brackish-water shrimp Crangon crangon
Hagerman, L.; Szaniawska, A. (1986). Behaviour, tolerance and anaerobic metabolism under hypoxia in the brackish-water shrimp Crangon crangon. Mar. Ecol. Prog. Ser. 34: 125-132. https://dx.doi.org/10.3354/meps034125
In: Marine Ecology Progress Series. Inter-Research: Oldendorf/Luhe. ISSN 0171-8630; e-ISSN 1616-1599, meer
|   |
| Abstract |
Behavioural and metabolic reactions of Crangon crangon L. were studied at different activity levels in shrimp exposed to various degrees of hypoxia. At 20°C, the normally buried C. crangon emerges from the sand at a PwO2 of 40 to 50 % saturation (20 %o S); at 9°C the emersion response occurs at PwO2 20 %. A swimming reaction was always noted at PwO2 30 to 40 % (20 %o S; 20°C). Regardless of salinity, survival was high down to PwO2 30 %. LT50, was strongly dependent on wO2 and salinity; thus at 10 %. S, wO2 10 %: LT50 = 4.5 h; at 20 %o S. wO2 10 %: LTSo = 6 h; at 10 %. S, wO2 20 %: LT50 = > 150 h. Circulating lactate was accumulated only at wO2 10 % saturation or lower. Normoxic lactate levels were ca 10 mg 100 ml-1 and increased in wO2 less than 10 % to 80 to 100 mg 100 ml-1 after 3 to 4 h. C. crangon will die quickly at this PwO2, unless higher oxygen tensions prevail rapidly. Return to normoxic conditions caused circulating lactate to be re-oxidised to normoxic levels within 5 to 6 h. When C. crangon was forced to swim in different PwO2 for up to 2 h the circulating lactate remained, regardless of the PwO2 (100 to 40 % sat.) at norrnoxic levels. Oxygen consumption (MO2) rose to varying degrees (5 to 70 % of routine MO2) when C. crangon was forced to swim for 2 h. No sign of oxygen debt was found after a swimming period. Due to a higher MO2 when exposed to wO2 of 40 to 50 %, swimming MO2 under these conditions rose only 10 to 15 %. During escape reactions C. crangon used its abdominal muscle, but after ca 15 contractions that muscle showed signs of fatigue. No increase in circulating lactate was found after such escape reactions. MO2 under escape reactions increased up to 211 % of routine MO2 at normoxic wO2. Here also the MO2 returned quickly to routine levels without any signs of oxygen debt. |
|
