Energetic savings and cardiovascular dynamics of a marine euryhaline fish (Myoxocephalus scorpius) in reduced salinity

AbstractFew studies have addressed how reduced water salinity affects cardiovascular and metabolic function in marine euryhaline fishes, despite its relevance for predicting impacts of natural salinity variations and ongoing climate change on marine fish populations. Here, shorthorn sculpin (Myoxocephalus scorpius) were subjected to different durations of reduced water salinity from 33 to 15 ppt. Routine metabolic rate decreased after short-term acclimation (4–9 days) to 15 ppt, which corresponded with similar reductions in cardiac output. Likewise, standard metabolic rate decreased after acute transition (3 h) from 33 to 15 ppt, suggesting a reduced energetic cost of osmoregulation at 15 ppt. Interestingly, gut blood flow remained unchanged across salinities, which contrasts with previous findings in freshwater euryhaline teleosts (e.g., rainbow trout) exposed to different salinities. Although plasma osmolality, [Na+], [Cl−] and [Ca2+] decreased in 15 ppt, there were no signs of cellular osmotic stress as plasma [K+], [hemoglobin] and hematocrit remained unchanged. Taken together, our data suggest that shorthorn sculpin are relatively weak plasma osmoregulators that apply a strategy whereby epithelial ion transport mechanisms are partially maintained across salinities, while plasma composition is allowed to fluctuate within certain ranges. This may have energetic benefits in environments where salinity naturally fluctuates, and could provide shorthorn sculpin with competitive advantages if salinity fluctuations intensify with climate change in the future.

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Temperature acclimation rate of aerobic scope and feeding metabolism in fishes: implications in a thermally extreme future

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.1490 ◽

2014 ◽

Vol 281 (1794) ◽

pp. 20141490 ◽

Cited By ~ 77

Author(s):

Erik Sandblom ◽

Albin Gräns ◽

Michael Axelsson ◽

Henrik Seth

Keyword(s):

Metabolic Rate ◽

Time Course ◽

Standard Metabolic Rate ◽

Temperature Acclimation ◽

Specific Dynamic Action ◽

Energetic Cost ◽

Aerobic Scope ◽

Postprandial Metabolism ◽

Myoxocephalus Scorpius ◽

Maximum Metabolic Rate

Temperature acclimation may offset the increased energy expenditure (standard metabolic rate, SMR) and reduced scope for activity (aerobic scope, AS) predicted to occur with local and global warming in fishes and other ectotherms. Yet, the time course and mechanisms of this process is little understood. Acclimation dynamics of SMR, maximum metabolic rate, AS and the specific dynamic action of feeding (SDA) were determined in shorthorn sculpin ( Myoxocephalus scorpius ) after transfer from 10°C to 16°C. SMR increased in the first week by 82% reducing AS to 55% of initial values, while peak postprandial metabolism was initially greater. This meant that the estimated AS during peak SDA approached zero, constraining digestion and leaving little room for additional aerobic processes. After eight weeks at 16°C, SMR was restored, while AS and the estimated AS during peak SDA recovered partly. Collectively, this demonstrated a considerable capacity for metabolic thermal compensation, which should be better incorporated into future models on organismal responses to climate change. A mathematical model based on the empirical data suggested that phenotypes with fast acclimation rates may be favoured by natural selection as the accumulated energetic cost of a slow acclimation rate increases in a warmer future with exacerbated thermal variations.

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Body temperature and standard metabolic rate of the female viviparous lizard Eremias multiocellata during reproduction

Canadian Journal of Zoology ◽

10.1139/z11-116 ◽

2012 ◽

Vol 90 (1) ◽

pp. 79-84 ◽

Cited By ~ 8

Author(s):

Feng Yue ◽

Xiao-Long Tang ◽

De-Jiu Zhang ◽

Xue-Feng Yan ◽

Ying Xin ◽

...

Keyword(s):

Body Temperature ◽

Metabolic Rate ◽

Ambient Temperature ◽

Energy Cost ◽

Energy Requirement ◽

Standard Metabolic Rate ◽

The Body ◽

Energetic Cost ◽

Pregnant Females ◽

Eremias Multiocellata

The body temperature (Tb) and standard metabolic rate (SMR) of female Eremias multiocellata Günther, 1872, a viviparous lizard, were measured at 25, 30, and 35 °C during pregnancy and after parturition to assess energy requirement of reproduction. The results showed that the Tbs of female lizards were slightly higher than actual ambient temperature in the 25 and 30 °C groups, while they were slightly lower than ambient temperature in the 35 °C group. Ambient temperature significantly affected SMR and gestation period of females. Energy requirement was constant in nonpregnant females, whereas it was increased in pregnant females. The maximal estimates of maintenance costs of pregnancy (MCP) were 4.219, 4.220, and 4.448 mg CO2·min–1, which accounted for 19.40%, 14.15%, and 12.32% of the total metabolic rate in the 25, 30, and 35 °C group, respectively. The results indicated the MCP was an important component of total energy cost for the lizard E. multiocellata and the MCP in this lizard incurs a relative fixed energetic cost irrespective of ambient temperature.

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Respiration in relation to ion uptake in the crayfish Austropotamobius pallipes (Lereboullet)

Journal of Experimental Biology ◽

10.1242/jeb.63.3.689 ◽

1975 ◽

Vol 63 (3) ◽

pp. 689-699

Author(s):

D. W. Sutcliffe ◽

T. R. Carrick

Keyword(s):

Metabolic Rate ◽

Ion Transport ◽

Standard Metabolic Rate ◽

Ion Uptake ◽

Energetic Cost ◽

O2 Uptake ◽

Thermodynamic Work ◽

Salt Depletion ◽

The Mean ◽

Free Media

1. O2 uptake was determined for periods of 23–46 h in salt-depleted crayfish held in deionized water (DW) or Na-free media at 10 degrees C. These media were replaced by artificial lakewater media (ALW) containing 0-2-0-6 mM Na and O2 uptake was again determined for periods of 24–66 h. 2. During net ion uptake in ALW the metabolic rate was either elevated or depressed. Standard metabolism in ALW altered by amounts equivalent to 0-1 - 15–5% (mean 6-4 (15) +/− 4–4% S. D.) of the metabolic rate measured during salt-depletion. On three occasions the metabolic rate was elevated by 22-0 - 66–7%, but some of this increase may have been due to locomotor activity. 3. The calculated values for thermodynamic work involved in ion transport were 0–056 - 0–268 J/10 g. h at 10 degrees C, or 1-5 - 7-2% of the mean standard metabolic rate. Most of the observed changes in metabolic rate lie within the limits of experimental error (ca. +/− 7%). Hence the energetic cost of ion transport is too small for direct measurement in intact crayfish.

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Transgenerational effects decrease larval resilience to ocean acidification and warming but juvenile European sea bass could benefit from higher temperatures in the NE Atlantic

10.1101/2021.11.15.468704 ◽

2021 ◽

Author(s):

Sarah Howald ◽

Marta Moyano ◽

Amélie Crespel ◽

Louise Cominassi ◽

Guy Claireaux ◽

...

Keyword(s):

Metabolic Rate ◽

Ocean Acidification ◽

Larval Growth ◽

Sea Bass ◽

Standard Metabolic Rate ◽

Routine Metabolic Rate ◽

Juvenile Growth ◽

European Sea Bass ◽

Larval Size ◽

Size At Metamorphosis

The aim of this study was to investigate the effect of ocean acidification (OA) and warming (OW) as well as the transgenerational effect of OA on larval and juvenile growth and metabolism of a large economically important fish species with a long generation time. Therefore we incubated European sea bass from Brittany (France) for two generations (>5 years in total) under current and predicted OA conditions (PCO2: 650 and 1700 μatm). In the F1 generation both OA condition were crossed with OW (temperature: 15-18 °C and 20-23 °C). We found that OA alone did not affect larval or juvenile growth and OW increased developmental time and growth rates, but OAW decreased larval size at metamorphosis. Larval routine metabolic rate (RMR) and juvenile standard metabolic rate (SMR) were significantly lower in cold compared to warm conditioned fish and also lower in F0 compared to F1 fish. We did not find any effect of OA on RMR or SMR. Juvenile PO2crit was not affected by OA, OW or OAW in both generations. We discuss the potential underlying mechanisms resulting in beneficial effects of OW on F1 larval growth and RMR and in resilience of F0 and F1 larvae and juveniles to OA, but on the other hand resulting in vulnerability of F1, but not F0 larvae to OAW. With regard to the ecological perspective, we conclude that recruitment of larvae and early juveniles to nursery areas might decrease under OAW conditions but individuals reaching juvenile phase might benefit from increased performance at higher temperatures.

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METABOLIC RATES (SMR, RMR, AMR, AND MMR) OF Oplegnathus fasciatus ON DIFFERENT TEMPERATURE AND SALINITY SETTINGS

Indonesian Aquaculture Journal ◽

10.15578/iaj.13.1.2018.23-29 ◽

2018 ◽

Vol 13 (1) ◽

pp. 23

Author(s):

Vitas Atmadi Prakoso ◽

Young Jin Chang

Keyword(s):

Metabolic Rate ◽

Standard Metabolic Rate ◽

External Factors ◽

Routine Metabolic Rate ◽

Metabolic Rates ◽

Marine Fish Species ◽

Oplegnathus Fasciatus ◽

Rock Bream ◽

Internal And External Factors ◽

Maximum Metabolic Rate

The metabolic rate of aquatic animals is closely related to oxygen concentration and influenced by internal and external factors. Despite its high value as marine fish species in South Korea, information on rock bream Oplegnathus fasciatus metabolism is scarcely available. This study observed the standard metabolic rate (SMR), routine metabolic rate (RMR), and active metabolic rate (AMR) of rock bream Oplegnathus fasciatus subjected to different temperature settings. Another observation was performed to find out the maximum metabolic rate (MMR) on rock bream subjected to different salinity settings. Fish (TL: 26.86 ± 0.29 cm and BW: 469.40 ± 38.21 g for SMR, RMR, and AMR measurement; TL: 26.7 ± 0.4 cm and BW: 451.0 ± 44.4 g for MMR measurement) were observed using respirometer (dimension = 30 cm × 20 cm × 20 cm; volume: 10.4 L) inside a recirculation systems. SMR, RMR, and AMR were measured at 15°C, 20°C, and 25°C. Meanwhile, MMR was measured at 15, 25, and 35 psu. The results showed that SMR, RMR, and AMR increased linearly by increasing the temperatures (SMR: 58.7 ± 3.2, 102.7 ± 4.3, and 157.1 ± 4.1 mg O2/kg/h at 15°C, 20°C, and 25°C, respectively; RMR: 66.0 ± 8.6, 112.6 ± 10.2, and 175.2 ± 21.3 mg O2/kg/h at 15°C, 20°C, and 25°C, respectively; AMR: 73.4 ± 7.4, 122.0 ± 6.3, and 196.7 ± 15.4 mg O2/kg/h at 15°C, 20°C, and 25°C, respectively), whilst MMR decreased by lowering salinity (48.5 ± 5.2, 61.1 ± 5.5, and 89.3 ± 14.7 mg O2/kg/hour at salinity of 15, 25, and 35 psu, respectively).

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Multigenerational exposure to elevated temperatures leads to a reduction in standard metabolic rate in the wild

10.1101/749986 ◽

2019 ◽

Author(s):

Natalie Pilakouta ◽

Shaun S. Killen ◽

Bjarni K. Kristjánsson ◽

Skúli Skúlason ◽

Jan Lindström ◽

...

Keyword(s):

Climate Change ◽

Gene Flow ◽

Metabolic Rate ◽

Elevated Temperatures ◽

General Pattern ◽

Standard Metabolic Rate ◽

List Type ◽

Geographic Scale ◽

Lower Standard ◽

Warming World

AbstractIn light of global climate change, there is a pressing need to understand and predict the capacity of populations to respond to rising temperatures. Metabolic rate is a key trait that is likely to influence the ability to cope with climate change. Yet, empirical and theoretical work on metabolic rate responses to temperature changes has so far produced mixed results and conflicting predictions.Our study addresses this issue using a novel approach of comparing fish populations in geothermally warmed lakes and adjacent ambient-temperature lakes in Iceland. This unique ‘natural experiment’ provides repeated and independent examples of populations experiencing contrasting thermal environments for many generations over a small geographic scale, thereby avoiding the confounding factors associated with latitudinal or elevational comparisons. Using Icelandic sticklebacks from three warm and three cold habitats, we measured individual metabolic rates across a range of acclimation temperatures to obtain reaction norms for each population.We found a general pattern for a lower standard metabolic rate in sticklebacks from warm habitats when measured at a common temperature, as predicted by Krogh’s rule. Metabolic rate differences between warm- and cold-habitat sticklebacks were more pronounced at more extreme acclimation temperatures, suggesting the release of cryptic genetic variation upon exposure to novel conditions, which can reveal hidden evolutionary potential. We also found a stronger divergence in metabolic rate between thermal habitats in allopatry than sympatry, indicating that gene flow may constrain physiological adaptation when dispersal between warm and cold habitats is possible.In sum, our study suggests that fish may diverge toward a lower standard metabolic rate in a warming world, but this might depend on connectivity and gene flow between different thermal habitats.

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Stability of physiological and behavioural determinants of performance in Arctic char (Salvelinus alpinus)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f01-050 ◽

2001 ◽

Vol 58 (5) ◽

pp. 961-968 ◽

Cited By ~ 55

Author(s):

C J Cutts ◽

C E Adams ◽

A Campbell

Keyword(s):

Metabolic Rate ◽

Competitive Ability ◽

Salvelinus Alpinus ◽

Standard Metabolic Rate ◽

Arctic Char ◽

Energetic Cost ◽

Behavioural Determinants ◽

Relative Differences ◽

Over Time ◽

Behavioural Dominance

The physiological and behavioural mechanisms that confer behavioural dominance are poorly understood. Although recent studies have shown a link between metabolism and dominance, these studies relied on single measurements of both, and assumed that inter-individual variation of physiology and behaviour were repeatable over time. This paper demonstrates that standard metabolic rate is a repeatable trait in Arctic char (Salvelinus alpinus L.) and that relative differences between individuals are consistent across a range of environmental conditions. Furthermore, there were positive associations between metabolic rate, aggression, and competitive ability that were also repeatable over time. However, there was no relationship between competitive ability (measured as feeding attempts) and subsequent growth. This may be due to an energetic cost of dominance: high rates of food capture were only attainable through high rates of effort. This, in addition to elevated aggression, was thought to exert an energetic cost that could not be fully offset by the increased food intake.

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Associations between metabolic traits and growth rate in brown trout ( Salmo trutta ) depend on thermal regime

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2021.1509 ◽

2021 ◽

Vol 288 (1959) ◽

pp. 20211509

Author(s):

Louise C. Archer ◽

Stephen A. Hutton ◽

Luke Harman ◽

W. Russell Poole ◽

Patrick Gargan ◽

...

Keyword(s):

Growth Rate ◽

Metabolic Rate ◽

Brown Trout ◽

Thermal Regime ◽

Salmo Trutta ◽

Standard Metabolic Rate ◽

Energetic Cost ◽

Fluctuating Selection ◽

Metabolic Traits ◽

Spatio Temporal

Metabolism defines the energetic cost of life, yet we still know relatively little about why intraspecific variation in metabolic rate arises and persists. Spatio-temporal variation in selection potentially maintains differences, but relationships between metabolic traits (standard metabolic rate (SMR), maximum metabolic rate (MMR), and aerobic scope) and fitness across contexts are unresolved. We show that associations between SMR, MMR, and growth rate (a key fitness-related trait) vary depending on the thermal regime (a potential selective agent) in offspring of wild-sampled brown trout from two populations reared for approximately 15 months in either a cool or warm (+1.8°C) regime. SMR was positively related to growth in the cool, but negatively related in the warm regime. The opposite patterns were found for MMR and growth associations (positive in warm, negative in the cool regime). Mean SMR, but not MMR, was lower in warm regimes within both populations (i.e. basal metabolic costs were reduced at higher temperatures), consistent with an adaptive acclimation response that optimizes growth. Metabolic phenotypes thus exhibited a thermally sensitive metabolic ‘floor’ and a less flexible metabolic ‘ceiling’. Our findings suggest a role for growth-related fluctuating selection in shaping patterns of metabolic variation that is likely important in adapting to climate change.

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