Temperature Acclimation of Mytilus Edulis With Reference to its Energy Budget

1971 ◽  
Vol 51 (4) ◽  
pp. 827-843 ◽  
Author(s):  
J. Widdows ◽  
B. L. Bayne
Keyword(s):  
Oxygen Consumption ◽  
Energy Balance ◽  
Cold Acclimation ◽  
Mytilus Edulis ◽  
Energy Budget ◽  
Filtration Rate ◽  
Physiological Stress ◽  
Assimilation Efficiency ◽  
Experimental Period ◽  
Temperature Acclimation

Mytilus edulis L. is shown to acclimate to high and low temperature under laboratory conditions. The warm and cold acclimation of oxygen consumption, filtration rate and assimilation efficiency are described for groups of animals maintained at three food-cell concentrations. Complete acclimation (Precht's type 2) of oxygen consumption and filtration rate occur within 14 days. There is no change in assimilation efficiency within the 28-day experimental period. The results are integrated and discussed in the context of a simple energy budget. In terms of the energy budget there exists a marked contrast between warm and cold acclimation. An “index of energy balance” is proposed in order to assess the state of the energy balance. When animals are fed above the maintenance requirement the energy budget remains in an equilibrium state during cold acclimation, whereas the acclimation to a warm temperature regime disrupts the balance and represents a physiological stress. During warm acclimation, prior to the re-establishment of an energy equilibrium the blood sugar level increases, suggesting that the animal is required to mobilize and utilize its energy reserves.

The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis

1984 ◽  
Vol 64 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Patricia C. Almada-Villela
Keyword(s):  
Growth Rate ◽  
Mytilus Edulis ◽  
High Salinity ◽  
Shell Growth ◽  
Experimental Period ◽  
Gradual Decline ◽  
Poor Growth ◽  
Term Response ◽  
Better Than

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.

scholarly journals Mitochondrial responses towards intermittent heat shocks in the Eastern Oyster, Crassostrea virginica

2021 ◽  
Author(s):  
Georges Hraoui ◽  
Sophie Breton ◽  
Gilles Miron ◽  
Luc H. Boudreau ◽  
Florence Hunter-Manseau ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Heat Shock ◽  
Crassostrea Virginica ◽  
Heat Waves ◽  
Physiological Stress ◽  
Eastern Oyster ◽  
Emission Rates ◽  
Mitochondrial Functions ◽  
Heat Shocks ◽  
Single Stress

Frequent heat waves caused by climate change can cause physiological stress in many animals, particularly in sessile ectotherms such as bivalves. Most studies characterizing thermal stress in bivalves focus on evaluating the responses to a single stress event. This does not accurately reflect the reality faced by bivalves which are often subject to intermittent heat waves. Here, we investigated the effect of intermittent heat stress on mitochondrial functions of Eastern oyster Crassostrea virginica which play a key role in setting ectotherms’ thermal tolerance. Specifically, we measured changes in mitochondrial oxygen consumption and H2O2 emission rates before, during and after intermittent 7.5°C heat shocks in oysters acclimated to 15°C and 22.5°C. Our results showed that oxygen consumption was impaired following the first heat shock at both acclimation temperatures. After the second heat shock, results for oysters acclimated to 15°C indicated a return to normal. However, oysters acclimated to 22.5°C struggled more with the compounding effects of intermittent heat shocks as denoted with an increase contribution of FAD-linked substrates to mitochondrial respiration as well as high levels of H2O2 emission rates. However, both acclimated populations showed signs of potential recovery ten days after the second heat shock, reflecting a surprising resilience to heat waves by C. virginica. Thus, this study highlights the important role of acclimation in oyster's capacity to weather intermittent heat shock.

Effect of fatty acid composition of dietary fat on energy balance and expenditure in hamsters

1989 ◽  
Vol 67 (9) ◽  
pp. 994-998 ◽  
Author(s):  
Peter J. H. Jones
Keyword(s):  
Oxygen Consumption ◽  
Energy Balance ◽  
Energy Expenditure ◽  
Fish Oil ◽  
Corn Oil ◽  
Dietary Fatty Acids ◽  
Metabolizable Energy ◽  
Before And After ◽  
Metabolizable Energy Intake ◽  
Energy Gains

The comparative effects of feeding diets containing corn, olive, coconut, or menhaden fish oil on efficiency of energy deposition and on short term energy expenditure were examined in growing hamsters. Diets comprising oils mixed with laboratory diets at 10% oil w/w were fed ad libitum for 3 weeks. Animals fed laboratory diets were used as controls. Body composition was determined before and after the feeding period using 3H2O distribution space. Oxygen consumption was measured in each animal during the final week. Weight gains of groups fed corn and olive oil diets exceeded those of the group fed laboratory diet alone (p < 0.05), although metabolizable energy intakes were similar across groups. Corn oil fed animals demonstrated higher carcass energy gains as fat compared with laboratory diet fed or menhaden oil fed groups. This was reflected in an increased fractional deposition of metabolizable energy intake in the group fed corn oil diet compared with the latter two groups. Fecal energy losses were lower in the group fed corn oil diet, and higher in the group fed laboratory diet alone, compared with other groups. Oxygen consumption did not differ between groups. These findings indicate that feeding dietary fish oil, compared with corn oil, favours energy substrate oxidation reducing the fraction of metabolizable energy partitioned for storage.Key words: energy balance, energy expenditure, dietary fatty acids, hamster.

Metabolic and Tissue Solute Changes Associated With Changes in the Freezing Tolerance of the Bivalve Mollusc Modiolus Demissus

1977 ◽  
Vol 69 (1) ◽  
pp. 1-12
Author(s):  
DENNIS J. MURPHY
Keyword(s):  
Oxygen Consumption ◽  
Low Temperature ◽  
Freezing Tolerance ◽  
Anaerobic Metabolism ◽  
Arrhenius Plot ◽  
Physiological Mechanism ◽  
Temperature Acclimation ◽  
Anaerobic Conditions ◽  
Rate Of Oxygen Consumption ◽  
Dependent Mechanism

1. A physiological mechanism responsible for increasing the freezing tolerance of the bivalve Modiolus demissus (Dillwyn) following low-temperature acclimation was demonstrated. 2. The rates of oxygen consumption of M. demissus acclimated to temperatures between 0 and 24 °C were presented as an Arrhenius plot. A change in slope occurred at 10 °C, suggesting that temperature alone was not responsible for the increased decline in the rate of oxygen consumption below 10 °C. 3. Low-temperature acclimation had no effect on blood Na+ or K+ concentrations but did reduce the concentration of blood Mg2+ and, in addition, resulted in the accumulation of end-products characteristic of anaerobic metabolism - tissue alanine and proline, and blood Ca2+. Furthermore, maintenance of M. demissus under anaerobic conditions increased freezing tolerance. 4. Taken together, these data indicate that the increased freezing tolerance of M. demissus acclimated to low temperatures involves a conversion to anaerobic metabolism. 5. The increase in blood Ca2+ following low-temperature acclimation was associated with the increased freezing tolerance. Finally, Mg2+ simulated the effect of Ca2+ on freezing tolerance, but was only 20% as effective. 6. These results suggest that a Ca2+-dependent mechanism responsible for increasing the freezing tolerance of M. demissus exists, and that the increase in blood Ca2+ is due to a conversion to anaerobic metabolism.

Digitalization of the Development of the Fuel and Energy Balance of Russia's Northern Territories

2020 ◽  
pp. 325-348
Author(s):  
Izabella Elyakova ◽  
Aleksandr Elyakov
Keyword(s):  
Control System ◽  
Energy Balance ◽  
Energy Budget ◽  
Digital Technologies ◽  
Research Practice ◽  
Production And Consumption ◽  
Entire Complex ◽  
The Republic ◽  
Northern Territories ◽  
Implementation Management

The urgency of the energy budget research practice in the Republic of Sakha (Yakutia) on settlements with software for effective formation, implementation, management, monitoring, analysis, evaluation, rapid response, and strategic management of the entire complex of the energy budget is substantiated. The chapter reveals the lack of problems of unified methodology for the development of the energy budget and the use of different fundamentals of its preparation. The necessity of using digital technologies to develop a control system for a complex network of production and consumption of fuel and energy resources is rationalized.

Cold acclimation of obese () mice: Effects on energy balance

Metabolism ◽  
1984 ◽  
Vol 33 (9) ◽  
pp. 853-857 ◽  
Author(s):  
Colleen K. Smith ◽  
Dale R. Romsos
Keyword(s):  
Energy Balance ◽  
Cold Acclimation ◽  
Obese Mice
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