Effects of a temperature increase on oxygen consumption of yellow freshwater eels exposed to high hydrostatic pressure

Abstract

SUMMARYOxygen consumption was measured in yellow freshwater eels, Anguilla anguilla, during exposure to a hydrostatic pressure (HP) of 101 atmosphere absolute (ATA) for 3 h, either with or without a 5°C increase in water temperature. It was found that concomitant increases in temperature and pressure resulted in an increase in oxygen consumption that was lower than when pressure alone was increased. When eels were acclimated to HP for 21 days and then submitted to a temperature increase of 5°C, this induced a significant increase in oxygen consumption but only during the first hour. It is therefore concluded that raising the water temperature during the first hours under pressure could counterbalance the pressure effects on membrane fluidity in a thermodynamic manner and thus help shallow-water fish acclimate to high pressure. In contrast, when acclimation processes are ended, the temperature effect disappears within 1 h.

Acclimation to predicted ocean warming through developmental plasticity in a tropical reef fish

“…This suggests that acclimation may be an important process whereby tropical reef fish can cope with increased average summer temperatures in the future without a loss of performance at winter temperatures. The reduction in RMR of $ 70 mg O 2 kg À1 h À1 in acclimated fish represented a Q 10 (the rate of change depending on temperature) reduction of 1.31, which is similar to that observed when acclimation in polar fishes occurs (Q 10 change: 0.62-1.29; Franklin et al, 2007;Robinson & Davison, 2008), but is less than that recorded for temperate species (Q 10 change: 1.55-3.97; Morris, 1965;Walsh et al, 1983;Sébert et al, 1995). This demonstrates that acclimation potential of some tropical fishes may not be as large as species that experience greater seasonal variation in maximum and minimum temperatures.…”

Physiological responses to acute temperature increase in European eels Anguilla anguilla infected with Anguillicola crassus

“…This is in line with our findings of a stable MCHC in both groups of eels exposed to temperature stress. Eels exposed to an increase in temperature have been shown to elevate oxygen consumption, indicating temperature-driven increases in metabolic rates (Sébert et al 1995). There is evidence to suggest that eels may preferentially use glucose as an energy substrate, which is unusual amongst teleosts (Kieffer et al 1998, Legate et al 2001.…”

Does hydrostatic pressure influence lumpfish (Cyclopterus lumpus) heart rate and its response to environmental challenges?

“…This finding was quite surprising as Scaion et al . (2008a) showed that temperature had a significant effect on the sensitivity of ṀO 2 to increases in hydrostatic pressure, and Sébert et al . (1995b) reported that exposing eels to a 5°C temperature increase (from 15°C to 20°C) concomitantly with an increase in pressure to ~101 bar reduced the acute increase in ṀO 2 by ~50%.…”

“…see Sébert and Barthélémy, 1985a , b ; Sébert and Macdonald, 1993 ; Speers-Roesch et al ., 2004 ; Vettier et al ., 2005 , 2006 ). However, to our knowledge, no studies have measured the physiological response of fish to hypoxia in combination with pressure and very few studies have examined the combined effects of temperature and pressure ( Sébert et al ., 1995a , b ; Scaion et al ., 2008a , b ). Further, even less is known about its effects on the cardiovascular system, and the published information is quite variable.…”