Respiratory metabolism studies on red-winged blackbird nestlings

1968 ◽  
Vol 46 (2) ◽  
pp. 223-233 ◽  
Author(s):  
M. I. Dyer
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Temperature Gradient ◽  
Respiratory Quotient ◽  
Environmental Temperature ◽  
Metabolic Response ◽  
Respiratory Metabolism ◽  
Nestling Period ◽  
Metabolic Reactions ◽  
Two Populations

Nestling red-winged blackbirds exhibited two distinct metabolic reactions to lowering temperatures. One group, which maintained homeothermic conditions, elevated its metabolism linearly according to a drop in ambient temperature and the second decreased its metabolic response in a curvilinear fashion. Core temperatures showed that although there was a progression toward the establishment of homeothermy throughout the nestling period, the birds could and did drop their core temperatures when the temperature gradient was too great to maintain constant body temperature. In some instances it is felt that oxygen consumption, and thus metabolism, was lowered before body temperature was suddenly dropped. No differences in the rates of metabolism could be found between upland and marshland populations; however, differences between values of the respiratory quotient for the two populations were found (p < 0.001). In addition differences in R.Q. values were found between well-developed nestlings practicing homeothermy and those that became hypothermic in response to lowering environmental temperature.

scholarly journals The metabolic response of the Bradypus sloth to temperature

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5600 ◽  
Author(s):  
Rebecca Naomi Cliffe ◽  
David Michael Scantlebury ◽  
Sarah Jane Kennedy ◽  
Judy Avey-Arroyo ◽  
Daniel Mindich ◽  
...  
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Energy Expenditure ◽  
High Power ◽  
Metabolic Response ◽  
Metabolic Responses ◽  
Metabolic Depression ◽  
Wide Range ◽  
Energetic Constraints ◽  
Power Costs

Poikilotherms and homeotherms have different, well-defined metabolic responses to ambient temperature (Ta), but both groups have high power costs at high temperatures. Sloths (Bradypus) are critically limited by rates of energy acquisition and it has previously been suggested that their unusual departure from homeothermy mitigates the associated costs. No studies, however, have examined how sloth body temperature and metabolic rate vary with Ta. Here we measured the oxygen consumption (VO2) of eight brown-throated sloths (B. variegatus) at variable Ta’s and found that VO2 indeed varied in an unusual manner with what appeared to be a reversal of the standard homeotherm pattern. Sloth VO2 increased with Ta, peaking in a metabolic plateau (nominal ‘thermally-active zone’ (TAZ)) before decreasing again at higher Ta values. We suggest that this pattern enables sloths to minimise energy expenditure over a wide range of conditions, which is likely to be crucial for survival in an animal that operates under severe energetic constraints. To our knowledge, this is the first evidence of a mammal provisionally invoking metabolic depression in response to increasing Ta’s, without entering into a state of torpor, aestivation or hibernation.

Physiological reactions of Caucasian and Bantu males in acute exposure to cold

1964 ◽  
Vol 19 (4) ◽  
pp. 583-592 ◽  
Author(s):  
C. H. Wyndham ◽  
J. S. Ward ◽  
N. B. Strydom ◽  
J. F. Morrison ◽  
C. G. Williams ◽  
...  
Keyword(s):  
Body Temperature ◽  
Ethnic Differences ◽  
Metabolic Response ◽  
Climatic Chamber ◽  
Air Temperatures ◽  
Metabolic Reactions ◽  
The Difference ◽  
Physiological Reactions ◽  
Average Skin ◽  
Skin Temperatures

Eleven men per sample of Caucasian and Bantu males were exposed for 2 hr in a climatic chamber at various air temperatures ranging from 5 to 27 C, and a wind velocity of 80–100 ft/min. When expressed per square meter surface area the metabolism of the Bantu was greater in the range above 18 C and below 6 C. Average skin temperatures were similar for both groups, but between 27 and 17 C the toe and finger temperatures of the Caucasians were significantly higher than that of the Bantu—the difference at 27 C being 5 C for the fingers and 3.6 C for the toes. Rectal temperatures of both groups were similar between 27 and 17 C. With the rectal temperatures at 27 C air temperature as the criterion, it was found that as the air temperatures decreased below the 27–17 C range the rectal temperatures of the Bantu fell linearly, while the rectal temperatures of the Caucasians rose steadily. There is no doubt that in certain ranges of air temperatures there are significant differences between the cold reactions of Caucasians and the Bantu. cold adaptation; ethnic differences in response to cold; metabolic and body temperature reactions to cold; metabolic response to body temperature; metabolic reactions of ethnic groups Submitted on July 15, 1963

The effects of activity, temperature and mass on the respiratory metabolism of the squid, Illex illecebrosus

1984 ◽  
Vol 64 (3) ◽  
pp. 535-543 ◽  
Author(s):  
M. E. DeMont ◽  
R. K. O'Dor
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Ambient Temperature ◽  
Environmental Temperature ◽  
Experimental Period ◽  
Respiratory Metabolism ◽  
Increase Oxygen Consumption ◽  
Activity Temperature

Oxygen consumption was measured in squid (Illex illecebrosus) ranging from 42·7 to 443·0 g. Ambient temperature increased from 8·3 °C to 18·2 °C during the experimental period. Resting rates were calculated by correcting for the percentage of time not spent in the resting posture. A 100 g squid resting at 13 °C has a predicted oxygen consumption of 31·3 ml/h, while a continuously swimming squid has an oxygen consumption of 125·0 ml/h. Oxygen consumption is almost directly proportional to body size. A 10° increase in environmental temperature would increase oxygen consumption for a squid of given mass by 6·7 times.

Polar bear locomotion: body temperature and energetic cost

1982 ◽  
Vol 60 (1) ◽  
pp. 40-44 ◽  
Author(s):  
R. J. Hurst ◽  
M. L. Leonard ◽  
P. D. Watts ◽  
P. Beckerton ◽  
N. A. Øritsland
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Polar Bear ◽  
Metabolic Response ◽  
Energetic Cost ◽  
Deep Body Temperature ◽  
Hunting Strategies ◽  
Relative Inability ◽  
Walking Speeds ◽  
Deep Body

The metabolic response of a 190-kg polar bear was tested at four different walking speeds within a respiration chamber mounted on a treadmill. Regressions of deep body temperature and oxygen consumption as a function of walking speed were determined. Equilibrium deep body temperature increased exponentially with speed of locomotion and indicated a relative inability to dissipate metabolic heat at high walking speeds. Metabolic rate, as measured by weight-specific oxygen consumption, was also best fit by a curvilinear equation and was twice that predicted by a general equation for quadruped locomotion. The apparent inefficiency of locomotion in polar bears suggests a compromise between thermoregulation, hunting strategies, and economy of transport.

EXERCISE AND TEMPERATURE REGULATION IN LEMMINGS AND RABBITS

1955 ◽  
Vol 33 (1) ◽  
pp. 428-435 ◽  
Author(s):  
J. S. Hart ◽  
O. Heroux
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Heat Production ◽  
Temperature Regulation ◽  
Thermal Equilibrium ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Temperature Changes ◽  
Extreme Cold ◽  
Environmental Temperatures

Oxygen consumption and body temperatures were determined in lemmings at environmental temperatures from 20 °C. to −10 °C. and in rabbits from 20 °C. to −50 °C. Body insulation indices were estimated as the ratio [Formula: see text]. In both species, increase in activity and decrease in temperature led to increases in oxygen consumption that were additive over the temperature range. Oxygen increments of work were independent of environmental temperature in the absence of progressive hypothermia. Work led to increases in body temperature at the upper environmental temperatures and to decreases in body temperature at the lower temperatures. In extreme cold, rabbits became progressively hypothermic during work and there was a decline in oxygen consumption. Body temperatures started to fall at environmental temperatures 18 °C. higher in working than in resting rabbits. Insulation was lower in working than in resting animals. During exercise there appears to be a readjustment of body temperature, insulation, and heat loss until thermal equilibrium is established. The regulation of heat production, within limits, seems to be independent of body-temperature changes during exercise.

Determinants and modeling of specific dynamic action for the Common Garter Snake (Thamnophis sirtalis)

2010 ◽  
Vol 88 (8) ◽  
pp. 808-820 ◽  
Author(s):  
Scott M. Bessler ◽  
Mary C. Stubblefield ◽  
G. R. Ultsch ◽  
Stephen M. Secor
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Body Mass ◽  
Metabolic Response ◽  
Specific Dynamic Action ◽  
Meal Size ◽  
Garter Snake ◽  
Thamnophis Sirtalis ◽  
Dynamic Action ◽  
The Common

Specific dynamic action (SDA), the cumulative energy expended on digestion and assimilation, can contribute significantly to individual daily energy expenditure (DEE). The Common Garter Snake (Thamnophis sirtalis (L., 1758)) is a widely distributed generalist predator that could experience considerable variation in SDA and hence the contribution of SDA to DEE. We examined the effects of meal size, meal type, and body temperature on the postprandial metabolic response and SDA of the Eastern Garter Snake ( Thamnophis sirtalis sirtalis (L., 1758)) and generated predictive models of SDA based on meal size, body mass, and body temperature, and separately based on meal energy. Postprandial peak in oxygen consumption, duration of significantly elevated oxygen consumption, and SDA increased with increasing meal size (5%–45% of body mass). Postprandial metabolic response digesting six different equal-size prey items varied significantly; vertebrate prey generated larger SDA responses than soft-bodied invertebrates. Increases in experimental temperature (15–35 °C) yielded a matched increase in postprandial peak in oxygen consumption and decrease in digestive duration. For a 1-month hypothetical feeding history for an adult T. sirtalis, the cumulative predicted SDA varied by 4.5% among the three models (minimal, intermediate, and maximal intake of prey) and averaged 8%, 22%, and 38% of DEE, respectively.

The influence of huddling and body size on the metabolic rate of the young pig

1960 ◽  
Vol 55 (1) ◽  
pp. 101-105 ◽  
Author(s):  
L. E. Mount
Keyword(s):  
Oxygen Consumption ◽  
Body Size ◽  
Energy Expenditure ◽  
Rectal Temperature ◽  
Energy Cost ◽  
Lower Energy ◽  
Environmental Temperature ◽  
Respiratory Metabolism ◽  
Young Pigs ◽  
Metabolism Chamber

1. The oxygen consumption of young pigs from 1 to 37 days of age has been measured in a closed circuit respiratory metabolism chamber, over the environmental temperature range 4–37° C.2. The values obtained for single pigs alone in the chamber have been compared with the results of measurements on groups of pigs 3–6 days of age taken together.3. It has been found that as environmental temperature falls below 30° C. and the grouped pigs huddle together, oxygen consumption per kg. for the group becomes smaller than values for single pigs of the same individual weight, and corresponds more with results from the larger single pig.4. Rectal temperature is maintained in pigs of the group at a lower energy cost than that required for the single pig, the saving in energy expenditure becoming proportionately greater as ambient temperature falls.5. These results are discussed in relation to body size and skin temperature.

Development of thermoregulation in Richardson's ground squirrel, Spermophilus richardsonii

1980 ◽  
Vol 58 (5) ◽  
pp. 890-895 ◽  
Author(s):  
Teresa M. Dolman
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Ground Squirrel ◽  
Metabolic Response ◽  
Thermal Conductance ◽  
Subsequent Growth ◽  
Normal Body Temperature ◽  
Normal Body ◽  
Spermophilus Richardsonii ◽  
Newborn Animals

Development of thermoregulation in Spermophilus richardsonii was investigated by determining the ability of neonates to maintain a normal body temperature when exposed to 30 and 25 °C, to maintain an elevated oxygen consumption (cubic centimetre oxygen per gram per hour) at 21 °C compared with that at 35 °C, and to move toward a warm object and assume curling postures when exposed to the cold. Newborn animals were essentially poikilothermic but by day 5 showed strong thermotaxis. By 30 days, the age of emergence from natal burrows, homeothermy had developed to the point at which normal body temperature could be maintained for at least 2 h at an ambient temperature of 25 °C. This process was correlated with improvements in heat production and heat retention. Subsequent growth was marked by a decreased metabolic response to cold (21 °C) owing to decreasing thermal conductance.

EXERCISE AND TEMPERATURE REGULATION IN LEMMINGS AND RABBITS

1955 ◽  
Vol 33 (3) ◽  
pp. 428-435 ◽  
Author(s):  
J. S. Hart ◽  
O. Heroux
Keyword(s):  
Oxygen Consumption ◽  
Body Temperature ◽  
Heat Production ◽  
Temperature Regulation ◽  
Thermal Equilibrium ◽  
Environmental Temperature ◽  
Body Temperatures ◽  
Temperature Changes ◽  
Extreme Cold ◽  
Environmental Temperatures

Oxygen consumption and body temperatures were determined in lemmings at environmental temperatures from 20 °C. to −10 °C. and in rabbits from 20 °C. to −50 °C. Body insulation indices were estimated as the ratio [Formula: see text]. In both species, increase in activity and decrease in temperature led to increases in oxygen consumption that were additive over the temperature range. Oxygen increments of work were independent of environmental temperature in the absence of progressive hypothermia. Work led to increases in body temperature at the upper environmental temperatures and to decreases in body temperature at the lower temperatures. In extreme cold, rabbits became progressively hypothermic during work and there was a decline in oxygen consumption. Body temperatures started to fall at environmental temperatures 18 °C. higher in working than in resting rabbits. Insulation was lower in working than in resting animals. During exercise there appears to be a readjustment of body temperature, insulation, and heat loss until thermal equilibrium is established. The regulation of heat production, within limits, seems to be independent of body-temperature changes during exercise.

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