Life on the edge: physiological problems in penaeid prawns Litopenaeus stylirostris, living on the low side of their thermopreferendum
Source: Marine Biology, Volume 154, Number 3, May 2008 , pp. 403-412(10)
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.
Document Type: Research Article
Affiliations: 1: Département Aquaculture en Calédonie, IFREMER, 101 promenade Roger Laroque, BP 2059, 98846, Nouméa, Nouvelle Calédonie, France, Email: email@example.com 2: Département Aquaculture en Calédonie, IFREMER, 101 promenade Roger Laroque, BP 2059, 98846, Nouméa, Nouvelle Calédonie, France 3: Laboratoire d’Ecophysiologie et Ecotoxicologie des Systèmes Aquatiques, UMR 5805, Université Bordeaux 1 and CNRS, Place du Dr B. Peyneau, 33120, Arcachon, France
Publication date: May 1, 2008