Life on the edge: physiological problems in penaeid prawns Litopenaeus stylirostris, living on the low side of their thermopreferendum
Wabete, N.; Chim, L.; Lemaire, P.; Massabuau, J.-C. (2008). Life on the edge: physiological problems in penaeid prawns Litopenaeus stylirostris, living on the low side of their thermopreferendum. Mar. Biol. (Berl.) 154(3): 403-412. http://dx.doi.org/10.1007/s00227-008-0931-1
In: Marine Biology: International Journal on Life in Oceans and Coastal Waters. Springer: Heidelberg; Berlin. ISSN 0025-3162; e-ISSN 1432-1793, more
|  |
| Authors | | Top |
- Wabete, N.
- Chim, L.
- Lemaire, P.
- Massabuau, J.-C.
|
|
|
| Abstract |
The underlying physiological mechanisms explaining why the adult penaeid prawn Litopenaeus stylirostris cannot successfully face heavy stressful events on the low edge of its thermopreferendum (20–22°C) were studied during the austral winter. Prawns were studied during recovery from net fishing and rapid transfer from outdoor earthen ponds into indoor facilities. This was assimilated to a predator–prey interaction. O2-consumption, hemolymph osmotic pressure (OPh), arterial O2 partial pressure (PO2), a–v O2-capacitance and mortality rates were analysed. Data were compared to similar challenges performed at 28°C during the austral summer. At 20–22°C, mortality of up to 70% was observed after 2 days whereas at 28°C, maximum mortality was 3–5%. Mortality occurred when OPh shifted towards equilibrium with seawater, the resting O2-consumption, the a–v O2-capacitance and the arterial PO2 went down to minimal values. These events can be counterbalanced by transiently hyper-oxygenating the hemolymph or by blocking the OPh shift in isosmotic water (Wabete et al. in Aquaculture 260:181–193, 2006): both led to a dramatic decrease in mortality. It is concluded that in penaeid prawns L. stylirostris, a mismatch between O2-demand and O2-supply contributes to setting the geographical limits for this animal species through an impairment of their hemolymph O2-carrying capacity during heavy stressful events like chasing by predators. |
|
