The magnitude of noradrenaline-induced thermogenesis in the bat (Myotis lucifugus) and its relation to arousal from hibernation

1968 ◽  
Vol 46 (5) ◽  
pp. 713-718 ◽  
Author(s):  
J. S. Hayward
Keyword(s):  
Oxygen Consumption ◽  
Heat Production ◽  
High Capacity ◽  
Fold Increase ◽  
Myotis Lucifugus ◽  
Maximal Rate ◽  
Significant Difference ◽  
Rate Of Oxygen Consumption ◽  
Very High

The effect of subcutaneously injected noradrenaline upon the rate of oxygen consumption of bats (Myotis lucifugus) has been evaluated. Maximal responses were obtained with doses between 2 and 15 mg noradrenaline/kg. These doses increased the oxygen consumption to a mean of 7.93 ml O2/g per h from a pretreatment mean of 0.75 ml O2/g per h, representing a 10.6-fold increase. A survey of the literature shows that the magnitude of this response exceeds by several times the magnitude of response observed for any other species. There was no significant difference between the responses of nonhibernated and hibernated bats. The maximal rate of thermogenesis during arousal from hibernation was a mean of 10.57 ml O2/g per h. In comparison with this value, the maximum noradrenaline-induced thermogenesis of hibernated bats was 8.62 ml O2/g per h. This provides an estimate (81.6%) of the involvement of noradrenaline-induced thermogenesis in the process of arousal from hibernation. These findings corroborate previously reported evidence that hibernating bats exhibit a very high capacity for nonshivering heat production.

Tolerance of estrogen-treated rats to acute cold exposure

1979 ◽  
Vol 47 (1) ◽  
pp. 59-66 ◽  
Author(s):  
M. J. Fregly ◽  
D. L. Kelleher ◽  
D. J. Black
Keyword(s):  
Oxygen Consumption ◽  
Cold Exposure ◽  
Previous Experiment ◽  
Female Rats ◽  
Control Group ◽  
Maximal Rate ◽  
Acute Cold Exposure ◽  
Exposure To Cold ◽  
Rate Of Oxygen Consumption ◽  
Rate Of Cooling

Female rats treated chronically with ethynylestradiol (36 micrograms/kg per day) alone, and in combination with the progestational agent, norethynodrel (253 micrograms/kg per day), cooled significantly faster than controls when lightly restrained and exposed to air at 5 degrees C. Rate of cooling of rats given only norethynodrel was similar to that of the control group. In other studies, rate of oxygen consumption was determined for all groups during acute exposure to cold (14 degrees C). All estrogen-treated groups achieved the same maximal rate of oxygen consumption as control and norethynodrel-treated groups during cold exposure, but cooled significantly faster. Two groups of female rats were treated chronically with ethynylestradiol at two separate doses (36 and 61 micrograms/kg per day). An untreated group served as controls. Rate of oxygen consumption of all animals were measured during restraint and exposure to cold (18 degrees C). The estrogen-treated groups again achieved the same maximal rate of oxygen consumption as the control group, but also cooled significantly faster despite the fact that the cold stress was less severe than in the previous experiment. That estrogen-treated rats cooled faster than controls in both studies despite achieving a maximal rate of heat production which did not differ from controls suggests that reduced cold tolerance of estrogen-treated rats may be related to increased heat loss.

Cardiovascular changes in the exercising emu

1983 ◽  
Vol 104 (1) ◽  
pp. 193-201 ◽  
Author(s):  
B. Grubb ◽  
D. D. Jorgensen ◽  
M. Conner
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Oxygen Consumption ◽  
Stroke Volume ◽  
Oxygen Content ◽  
Body Mass ◽  
Fold Increase ◽  
Exercise Heart Rate ◽  
Rate Of Oxygen Consumption ◽  
Cardiovascular Variables

Cardiovascular variables were studied as a function of oxygen consumption in the emu, a large, flightless ratite bird well suited to treadmill exercise. At the highest level of exercise, the birds' rate of oxygen consumption (VO2) was approximately 11.4 times the resting level (4.2 ml kg-1 min-1). Cardiac output was linearly related to VO2, increasing 9.5 ml for each 1 ml increase in oxygen consumption. The increase in cardiac output is similar to that in other birds, but appears to be larger than in mammals. The venous oxygen content dropped during exercise, thus increasing the arteriovenous oxygen content difference. At the highest levels of exercise, heart rate showed a 3.9-fold increase over the resting rate (45.8 beats min-1). The mean resting specific stroke volume was 1.5 ml per kg body mass, which is larger than shown by most mammals. However, birds have larger hearts relative to body mass than do mammals, and stroke volume expressed per gram of heart (0.18 ml g-1) is similar to that for mammals. Stroke volume showed a 1.8-fold increase as a result of exercise in the emus, but a change in heart rate plays a greater role in increasing cardiac output during exercise.

Osmotic balance and respiration in the hermit crab, Pagurus bernhardus, exposed to fluctuating salinities

1978 ◽  
Vol 58 (4) ◽  
pp. 869-876 ◽  
Author(s):  
Sandra E. Shumway
Keyword(s):  
Oxygen Consumption ◽  
Sea Water ◽  
External Medium ◽  
Temporary Increase ◽  
Tissue Water ◽  
Low Salinity ◽  
Significant Difference ◽  
Rate Of Oxygen Consumption ◽  
Osmotic Balance ◽  
Pagurus Bernhardus

Specimens of Pagurus bernhardus (with and without shells) were exposed to both gradual (sinusoidal) and abrupt (square-wave) salinity fluctuations and changes in haemolymph osmolality, tissue water content and oxygen consumption monitored. Oxygen consumption was also monitored under steady-state conditions; under these conditions there was no significant difference between the rate of oxygen consumption by animals with shells and animals without shells. Oxygen consumption was found to vary with body weight according to the equation O2 consumption = 0·292 W0·668. During exposure to fluctuating salinities the crabs with shells were seen to increase loco-motory activity when the external medium declined to approximately 75% sea water. Haemolymph osmolality values followed the same pattern of change as the external medium; the haemolymph of crabs without shells became significantly more dilute during exposure to low salinity than did that of crabs with shells. P. bernhardus showed significant increases and decreases in hydration level as salinities fell and rose respectively. Crabs with shells showed a marked temporary increase in oxygen consumption when the external medium declined to approximately 75% sea water; crabs without shells showed no such response. The importance of the shell as a means of protection against dilute media is discussed.

scholarly journals ON THE RATE OF OXYGEN CONSUMPTION BY FERTILIZED AND UNFERTILIZED EGGS

1931 ◽  
Vol 15 (2) ◽  
pp. 167-182 ◽  
Author(s):  
D. M. Whitaker
Keyword(s):  
Oxygen Consumption ◽  
Cell Division ◽  
Fucus Vesiculosus ◽  
High Rate ◽  
Rate Of Oxygen Consumption ◽  
C 50 ◽  
Very High

1. The unfertilized eggs of Fucus vesiculosus, in the dark, consume about 5.2 mm.3 O2 per hour per 10 mm.3 eggs. 2. With an illumination of 100,000 foot candles in photosynthesis they liberate more than twice as much oxygen as they consume. 3. The actively swimming antherozoids or sperm of Fucus consume oxygen at a very high rate: 25.5 mm.3 O2 per hour per 10 mm.3 antherozoids. 4. Immediately following fertilization, in the dark, the Fucus eggs increase the rate of oxygen consumption to about 190 per cent of the prefertilization rate. 5. This rate for fertilized eggs, about 190 per cent, is maintained uniformly for 13 or 14 hours, after which there is a barely perceptible rise until 24 hours (when measurements ceased). At 18°C. 50 per cent of the spores in a population have completed the first cell division about 15 hours after fertilization.

The Oxygen Consumption of Flies During Flight

1940 ◽  
Vol 17 (4) ◽  
pp. 402-407 ◽  
Author(s):  
R. A. DAVIS ◽  
G. FRAENKEL
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Lucilia Sericata ◽  
Pure Oxygen ◽  
Blow Fly ◽  
Significant Difference ◽  
Rate Of Oxygen Consumption ◽  
Wet Weight

A method is described by which the oxygen uptake of the blow-fly, Lucilia sericata Mg., was measured during flight manometrically in a Warburg and in a Barcroft type of apparatus. The average oxygen consumption in air for all the flies used was 95·580 c.c. per g. wet weight per hour. When flying in pure oxygen the rate of oxygen consumption showed no significant difference; in oxygen-nitrogen mixtures, containing 10 and 5% oxygen, the rate was considerably less than in air.

Cellular oxygen consumption depends on body mass

1995 ◽  
Vol 269 (1) ◽  
pp. R226-R228 ◽  
Author(s):  
R. K. Porter ◽  
M. D. Brand
Keyword(s):  
Oxygen Consumption ◽  
Body Mass ◽  
Metabolic Activity ◽  
Oxygen Consumption Rate ◽  
Consumption Rate ◽  
Fold Increase ◽  
Standard Metabolic Rate ◽  
Tissue Slices ◽  
Rate Of Oxygen Consumption ◽  
Cellular Oxygen

Hepatocytes were isolated from nine species of mammal of different body mass (and standard metabolic rate). The cells were incubated under identical conditions and oxygen consumption measured. The rate of oxygen consumption (per unit mass of cells) scaled with body mass with exponent -0.18. In general, there was a 5.5-fold decrease in oxygen consumption rate with a 12,500-fold increase in body mass. The decrease in oxygen consumption rate was not due to an increase in cell volume with increasing body mass but to a decrease in intrinsic metabolic activity of the cells. This novel finding confirms and explains the decrease in oxygen consumption rate measured in tissue slices from larger mammals by H. A. Krebs (Biochim. Biophys. Acta 4: 249-269, 1950) and recently by P. Couture and A. J. Hulbert [Am. J. Physiol. 268 (Regulatory Integrative Comp. Physiol. 37): R641-R650, 1995].

The metabolic cost of birdsong production

2001 ◽  
Vol 204 (19) ◽  
pp. 3379-3388 ◽  
Author(s):  
Kerstin Oberweger ◽  
Franz Goller
Keyword(s):  
Oxygen Consumption ◽  
Sound Intensity ◽  
Metabolic Cost ◽  
Fold Increase ◽  
Zebra Finches ◽  
European Starlings ◽  
Temporal Complexity ◽  
Complex Song ◽  
Rate Of Oxygen Consumption ◽  
Song Production

SUMMARY The metabolic cost of birdsong production has not been studied in detail but is of importance in our understanding of how selective pressures shape song behavior. We measured rates of oxygen consumption during song in three songbird species, zebra finches (Taeniopygia guttata), Waterslager canaries (Serinus canaria) and European starlings (Sturnus vulgaris). These species sing songs with different acoustic and temporal characteristics: short stereotyped song (zebra finch), long song with high temporal complexity (canary) and long song with high acoustic, but low temporal, complexity (starling). In all three species, song slightly increased the rate of oxygen consumption over pre-song levels (1.02–1.36-fold). In zebra finches, the metabolic cost per song motif averaged 1.2 μl g–1. This cost per motif did not change over the range of song duration measured for the four individuals. Surprisingly, the metabolic cost of song production in the species with the temporally most complex song, the canary, was no greater than in the other two species. In starlings, a 16 dB increase in sound intensity was accompanied by a 1.16-fold increase in the rate of oxygen consumption. These data indicate that the metabolic cost of song production in the songbird species studied is no higher than that for other types of vocal behavior in various bird groups. Our analysis shows that the metabolic cost of singing is also similar to that of calling in frogs and of human speech production. However, difficulties with measurements on freely behaving birds in a small respirometry chamber limit the depth of analysis that is possible.

scholarly journals THE OXYGEN CONSUMPTION OF ESCHERICHIA COLI DURING THE LAG AND LOGARITHMIC PHASES OF GROWTH

1932 ◽  
Vol 15 (6) ◽  
pp. 691-708 ◽  
Author(s):  
Donald S. Martin
Keyword(s):  
Escherichia Coli ◽  
Oxygen Consumption ◽  
Surface Area ◽  
Growth Curve ◽  
Heat Production ◽  
Lag Phase ◽  
Maximum Oxygen Consumption ◽  
Average Cell ◽  
Co2 Output ◽  
Rate Of Oxygen Consumption

The oxygen consumption of rapidly growing cultures of Esch. coli (S) have been measured by means of Fenn's respirometer. The rate of oxygen consumption of a growing culture uniformly attains a phase of logarithmic increase before the growth curve of the organisms becomes logarithmic. The rate of oxygen consumption per cell increases rapidly from the time of inoculation to a point of maximum respiration near the end of the lag phase of the growth curve, followed by a gradual decrease in the respiratory rate. The surface area of the average cell when plotted against time passes through a point of maximum surface area which coincides with the point of maximum oxygen consumption per cell. Figures obtained by different methods, CO2 output and heat production when reduced to the same units, agree remarkably well.

scholarly journals THE OXYGEN CONSUMPTION OF FROG NERVE DURING STIMULATION

1927 ◽  
Vol 10 (5) ◽  
pp. 767-779 ◽  
Author(s):  
Wallace O. Fenn
Keyword(s):  
Oxygen Consumption ◽  
Sciatic Nerve ◽  
Oxygen Tension ◽  
Heat Production ◽  
Nerve Impulse ◽  
Excess Oxygen ◽  
Causal Connection ◽  
Cent Increase ◽  
Rate Of Oxygen Consumption ◽  
Frequency Of Stimulation

1. The resting rate of oxygen consumption of the excised sciatic nerve of the frog is 1.23 c.mm. of oxygen per gm. of nerve per minute. 2. During stimulation with an induction coil with 100 make and 100 break shocks per second there is an excess oxygen consumption amounting on the average to 0.32 c.mm. of oxygen per gm. of nerve per minute of stimulation, or a 26 per cent increase over the resting rate. 3. The magnitude of the excess oxygen consumption in stimulation, in agreement with the all-or-none law, is not markedly influenced by considerable variations in the intensity of stimulation. 4. Increasing the frequency of stimulation from 100 to 200 shocks per second increases the extra oxygen used only 1.12–1.18 times. The same change in frequency of stimulation increases the negative variation 1.15 times and the heat production about 1.25 times (Hill). 5. This parallelism between the excess oxygen and the negative variation argues definitely for some causal connection between the excess oxygen and the nerve impulse itself. 6. Calculation shows that the oxygen tension inside these nerves was not zero.

Estimation of the rate of oxygen consumption of the common eider duck (Somateria mollissima), with some measurements of heart rate during voluntary dives

2000 ◽  
Vol 203 (18) ◽  
pp. 2819-2832 ◽  
Author(s):  
P.A. Hawkins ◽  
P.J. Butler ◽  
A.J. Woakes ◽  
J.R. Speakman
Keyword(s):  
Heart Rate ◽  
Oxygen Consumption ◽  
Individual Variability ◽  
Common Eider ◽  
Somateria Mollissima ◽  
Doubly Labelled Water ◽  
Mean Values ◽  
Significant Difference ◽  
Rate Of Oxygen Consumption ◽  
The Common

The relationship between heart rate (f(H)) and rate of oxygen consumption (V(O2)) was established for a marine diving bird, the common eider duck (Somateria mollissima), during steady-state swimming and running exercise. Both variables increased exponentially with speed during swimming and in a linear fashion during running. Eleven linear regressions of V(O2) (ml kg(−1)min(−1)) on f(H) (beats min(−1)) were obtained: five by swimming and six by running the birds. The common regression was described by V(O2)=10.1 + 0.15f(H) (r(2)=0.46, N=272, P<0.0001). The accuracy of this relationship for predicting mean V(O2) was determined for a group of six birds by recording f(H) continuously over a 2-day period and comparing estimated V(O2) obtained using the common regression with (i) V(O2) estimated using the doubly labelled water technique (DLW) and (ii) V(O2) measured using respirometry. A two-pool model produced the most accurate estimated V(O2) using DLW. Because of individual variability within mean values of V(O2) estimated using both techniques, there was no significant difference between mean V(O2) estimated using f(H) or DLW and measured V(O2) values (P>0.2), although individual errors were substantially less when f(H) was used rather than DLW to estimate V(O2). Both techniques are, however, only suitable for estimating mean V(O2) for a group of animals, not for individuals.Heart rate and behaviour were monitored during a bout of 63 voluntary dives by one female bird in an indoor tank 1.7 m deep. Tachycardia occurred both in anticipation of and following each dive. Heart rate decreased before submersion but was above resting values for the whole of the dive cycle. Mean f(H) at mean dive duration was significantly greater than f(H) while swimming at maximum sustainable surface speeds. Heart rate was used to estimate mean V(O2) during the dive cycle and to predict aerobic dive limit (ADL) for shallow dives.

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