Endogenous Biorhythms of Mass Specific Rate of Oxygen Consumption in Planorbarius corneus (Planorbidae, Gastropoda) Individual Development

2020 ◽  
Vol 51 (4) ◽  
pp. 255-260
Author(s):  
A. A. Zotin
Keyword(s):  
Oxygen Consumption ◽  
Individual Development ◽  
Specific Rate ◽  
Planorbarius Corneus ◽  
Rate Of Oxygen Consumption

Factorial scopes of cardio-metabolic variables remain constant with changes in body temperature in the varanid lizard, Varanus rosenbergi

2005 ◽  
Vol 288 (4) ◽  
pp. R992-R997 ◽  
Author(s):  
T. D. Clark ◽  
T. Wang ◽  
P. J. Butler ◽  
P. B. Frappell
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Oxygen Affinity ◽  
Aerobic Performance ◽  
Specific Rate ◽  
Aerobic Scope ◽  
Thermal Dependence ◽  
Hemoglobin Oxygen Affinity ◽  
Rate Of Oxygen Consumption ◽  
Metabolic Performance

The majority of information concerning the cardio-metabolic performance of varanids during exercise is limited to a few species at their preferred body temperature (Tb) even though, being ectotherms, varanids naturally experience rather large changes in Tb. Although it is well established that absolute aerobic scope declines with decreasing Tb, it is not known whether changes in cardiac output (V̇b) and/or tissue oxygen extraction, (CaO2 − Cv�[Formula: see text]), are in proportion to the rate of oxygen consumption (V̇o2). To test this, we studied six Rosenberg's goannas ( Varanus rosenbergi) while at rest and while maximally exercising on a treadmill both at 25 and 36°C. During maximum exercise both at 25 and 36°C, mass-specific rate of oxygen consumption (V̇o2kg) increased with an absolute scope of 8.5 ml min−1 kg−1 and 15.7 ml min−1 kg−1, respectively. Interestingly, the factorial aerobic scope was temperature-independent and remained at 7.0 which, at each Tb, was primarily the result of an increase in V̇bkg, governed by approximate twofold increases both in heart rate ( fH) and cardiac stroke volume (VSkg). Both at 25°C and 36°C, the increase in V̇bkg alone was not sufficient to provide all of the additional oxygen required to attain maximal V̇o2kg, as indicated by a decrease in the blood convection requirement V̇bkg/V̇o2kg; hence, there was a compensatory twofold increase in (CaO2 − [Formula: see text]). Although associated with an increase in hemoglobin-oxygen affinity, a decrease in Tb did not impair unloading of oxygen at the tissues and act to reduce (CaO2 − Cv�[Formula: see text]); both CaO2 and Cv�[Formula: see text] were maintained across Tb. The change in V̇o2kg with Tb, therefore, is solely reliant on the thermal dependence of V̇bkg. Maintaining a high factorial aerobic scope across a range of Tb confers an advantage in that cooler animals can achieve higher absolute aerobic scopes and presumably improved aerobic performance than would otherwise be achievable.

Energetics of surface swimming in Brandt's cormorants (Phalacrocorax penicillatus brandt)

2000 ◽  
Vol 203 (24) ◽  
pp. 3727-3731 ◽  
Author(s):  
A. Ancel ◽  
L.N. Starke ◽  
P.J. Ponganis ◽  
R. Van Dam ◽  
G.L. Kooyman
Keyword(s):  
Oxygen Consumption ◽  
Metabolic Rate ◽  
Resting Metabolic Rate ◽  
Energy Requirements ◽  
Swimming Velocity ◽  
Specific Rate ◽  
Cost Of Transport ◽  
Metabolic Chamber ◽  
Rate Of Oxygen Consumption ◽  
The Cost

The energy requirements of Brandt's cormorants (Phalacrocorax penicillatus) during surface swimming were measured in birds swimming under a metabolic chamber in a water flume. From the oxygen consumption recordings, we extrapolated the metabolic rate and cost of transport at water speeds ranging from 0 to 1.3 m s(−)(1). In still water, the birds' mean mass-specific rate of oxygen consumption (V(O2)) while floating at the surface was 20.2 ml O(2)min(−)(1)kg(−)(1), 2.1 times the predicted resting metabolic rate. During steady-state voluntary swimming against a flow, their V(O2) increased with water speed, reaching 74 ml O(2)min(−)(1)kg(−)(1) at 1.3 m s(−)(1), which corresponded to an increase in metabolic rate from 11 to 25 W kg(−)(1). The cost of transport decreased with swimming velocity, approaching a minimum of 19 J kg(−)(1)m(−)(1) for a swimming speed of 1.3 m s(−)(1). Surface swimming in the cormorant costs approximately 18 % less than sub-surface swimming. This confirms similar findings in tufted ducks (Aythya fuligula) and supports the hypothesis that increased energy requirements are necessary in these birds during diving to overcome buoyancy and heat loss during submergence.

scholarly journals The relationship between heart rate and rate of oxygen consumption in Galapagos marine iguanas (Amblyrhynchus cristatus) at two different temperatures

2002 ◽  
Vol 205 (13) ◽  
pp. 1917-1924 ◽  
Author(s):  
Patrick J. Butler ◽  
Peter B. Frappell ◽  
Tobias Wang ◽  
Martin Wikelski
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Venous Blood ◽  
Mixed Venous Blood ◽  
Specific Rate ◽  
Amblyrhynchus Cristatus ◽  
Exercise Period ◽  
Rate Of Oxygen Consumption ◽  
Marine Iguanas ◽  
The Difference

SUMMARY To enable the use of heart rate (fH) for estimating field metabolic rate (FMR) in free-ranging Galapagos marine iguanas Amblyrhynchus cristatus, we determined the relationships between fH and mass-specific rate of oxygen consumption(sV̇O2) in seven iguanas before and during exercise on a treadmill and during the post-exercise period. The experiments were conducted at 27 and 35°C, which are the temperatures that represent the lowest and highest average body temperatures of these animals in the field during summer. There were linear and significant relationships between fH and sV̇O2 at both temperatures (r2=0.86 and 0.91 at 27°C and 36°C,respectively). The slopes of the two regression lines did not differ, but there were significant differences in their intercepts. Thus, while heart rate can be used to predict FMR, the effects of temperature on the intercept of the regression must be taken into account when converting fH to sV̇O2. On the basis of our data, this can be achieved by applying the following formula: \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \[\mathrm{s}{\dot{V}}_{\mathrm{o}_{2}}=0.0113f\mathrm{H}-0.2983\mathrm{Q}_{10}^{\frac{(T_{\mathrm{b}}-27)}{10}}.\] \end{document}The increase in sV̇O2 with elevated body temperature results from an increase in fH, with no significant change in mass-specific oxygen pulse (sO2 pulse;cardiac stroke volume times the difference in oxygen content between arterial and mixed venous blood). However, during exercise at both temperatures,increases in fH are insufficient to provide all of the additional O2 required and there are also significant increases in the sO2 pulses. This creates the situation whereby the same fH at the two temperatures can represent different values of sV̇O2.

Heart rate and rate of oxygen consumption of exercising macaroni penguins

2001 ◽  
Vol 204 (4) ◽  
pp. 673-684 ◽  
Author(s):  
J.A. Green ◽  
P.J. Butler ◽  
A.J. Woakes ◽  
I.L. Boyd ◽  
R.L. Holder
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Average Error ◽  
Specific Rate ◽  
Variable Speed ◽  
Treadmill Speed ◽  
Eudyptes Chrysolophus ◽  
Rate Of Oxygen Consumption ◽  
Free Ranging ◽  
The Relationship

Twenty-four macaroni penguins (Eudyptes chrysolophus) from three groups, breeding males (N=9), breeding females (N=9) and moulting females (N=6), were exercised on a variable-speed treadmill. Heart rate (fH) and mass-specific rate of oxygen consumption (sVO2) were recorded from the animals, and both fh and sVO2 were found to increase linearly with increasing treadmill speed. A linear regression equation described the relationship between fh and sVO2 for each individual. There were no significant differences in these regressions between breeding and moulting females. There were significant differences in these relationships between all females and breeding males. fH and s VO2 were recorded from five of these animals for a total of 24 h. When fh was used to predict sVO2 for the 24 h period using the derived regressions, the estimate was not significantly different from the measured values, with an average error of −2.1 %. When fh was used to predict sVO2 for the 5 min intervals used for the calibration in all 24 birds, the estimate was not significantly different from the observed values, and the average error was only +0.47 %. Since the fH/sVO2 relationship was the same during periods of the annual cycle when the animals were inactive/fasting and active/foraging, it seems reasonable that, as long as sex differences are taken into account, fh can be used to predict the metabolic rates of free-ranging macaroni penguins all year round.

scholarly journals Recovery heat in muscular contraction without lactic acid formation

1931 ◽  
Vol 108 (757) ◽  
pp. 279-301 ◽  
Keyword(s):  
Acetic Acid ◽  
Oxygen Consumption ◽  
Lactic Acid ◽  
Muscular Contraction ◽  
Acid Formation ◽  
Anaerobic Conditions ◽  
Spontaneous Breakdown ◽  
Rate Of Oxygen Consumption ◽  
Resting Muscle

In a comparison of muscles poisoned with mono-iodo-acetic acid (IAA) in the presence and in the absence of oxygen respectively, Lundsgaard (1930) found:- (1) That the spontaneous breakdown of phosphagen in poisoned resting muscle is much more rapid under anaerobic conditions. (2) That the onset of the characteristic contracture produced by IAA is accompanied always by an increase in the rate of oxygen consumption.

Proximal tubule dysfunction in cystine-loaded tubules: effect of phosphate and metabolic substrates

1996 ◽  
Vol 271 (3) ◽  
pp. F717-F722
Author(s):  
G. Bajaj ◽  
M. Baum
Keyword(s):  
Oxygen Consumption ◽  
Proximal Tubule ◽  
Tricarboxylic Acid Cycle ◽  
Dimethyl Ester ◽  
Proximal Tubules ◽  
Intracellular Atp ◽  
Metabolic Substrates ◽  
Rate Of Oxygen Consumption ◽  
Intracellular Phosphate

Intracellular cystine loading by use of cystine dimethyl ester (CDME) results in a generalized inhibition in proximal tubule transport due, in part, to a decrease in intracellular ATP. The present study examined the importance of phosphate and metabolic substrates in the proximal tubule dysfunction produced by cystine loading. Proximal tubule intracellular phosphorus was 1.8 +/- 0.1 in control tubules and 1.1 +/- 0.1 nmol/mg protein in proximal tubules incubated in vitro with CDME P < 0.001). Infusion of sodium phosphate in rabbits and subsequent incubation of proximal tubules with a high-phosphate medium attenuated the decrease in proximal tubule respiration and prevented the decrease in intracellular ATP with cystine loading. Tricarboxylic acid cycle intermediates have been shown to preserve oxidative metabolism in phosphate-depleted proximal tubules. In proximal tubules incubated with either 1 mM valerate or butyrate, there was a 42 and 34% reduction (both P < 0.05) in the rate of oxygen consumption with cystine loading. However, tubules incubated with 1 mM succinate or citrate had only a 13 and 14% P = NS) reduction in the rate of oxygen consumption, respectively. These data are consistent with a limitation of intracellular phosphate in the pathogenesis of the proximal tubule dysfunction with cystine loading.

Viability and respiratory activity ofPseudomonas syringaecells starved in buffer

1995 ◽  
Vol 41 (4-5) ◽  
pp. 372-377 ◽  
Author(s):  
João P. S. Cabral
Keyword(s):  
Oxygen Consumption ◽  
Electron Transport ◽  
Pseudomonas Syringae ◽  
Respiratory Activity ◽  
Bacterial Cells ◽  
Intact Cells ◽  
Rate Of Oxygen Consumption ◽  
Metabolic Activities ◽  
Different Levels ◽  
Number Of Cells

Pseudomonas syringae cells starved in buffer released orcinol-reactive molecules and materials that absorbed ultraviolet light. The number of cells culturable in nutrient medium decreased more rapidly than the number of intact particles determined by microscopy. The results suggested that starvation resulted in the lysis of an increasing number of cells, and that a fraction of the intact particles were not culturable. Starvation also resulted in a decrease in the rate of oxygen consumption with acetate, glycerol, and succinate, but at different levels. Whereas the respiration of acetate and glycerol decreased concomitantly with culturability, the respiration of succinate decreased to levels similar to the concentration of intact cells, suggesting that all intact particles respired the succinate, but only the culturable cells respired the acetate and glycerol. The results suggest that measuring the activity of the electron-transport system can overestimate the viability of starved bacterial cells, and that complex metabolic activities such as the respiration of acetate and glycerol are probably better suited for the evaluation of this parameter.Key words: Pseudomonas syringae, starvation, culturability, viability, respiration.

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