Energy savings from vocal regulation of ambient temperature by 3-day-old domestic chicks

1996 ◽  
Vol 74 (4) ◽  
pp. 599-605 ◽  
Author(s):  
Anton Espira ◽  
Roger M. Evans

Precocial domestic chicks (Gallus domesticus) become endothermic at or soon after hatching, but when chilled still vocalize to solicit heat from a parent or surrogate. In this study, we examined the potential energy savings resulting from vocal solicitation of heat by comparing the oxygen consumption of 3-day-old chicks facing a cold challenge of 20 °C with and without the option of regulating ambient temperature by vocally soliciting 2-min periods of rewarming at 35 °C from a surrogate parent in the laboratory. Body temperature was unaffected by vocal regulation, but the thermal gradient between body and ambient temperature was reduced by 5.0 ± 0.4 °C (mean ± SE). Mass-specific oxygen consumption [Formula: see text] increased by 62.5% to a near steady state mean of 3.64 mL∙g−1∙h−1 during constant chilling at 20 °C, but increased by only 48.1%, to 3.08 mL∙g−1∙h−1, during vocal regulation. Relative to chilled controls, vocally regulating chicks had a mean net energy saving of 15.4% during the final, stable 15 min of testing. Vocal solicitation of heat from a brooding parent seems likely to be an important means of saving energy expended in thermoregulation in some precocial species when young chicks are exposed to low ambient temperatures under natural conditions.

1960 ◽  
Vol 199 (2) ◽  
pp. 243-245 ◽  
Author(s):  
H. A. Leon ◽  
S. F. Cook

The oxygen consumption of male Long-Evans rats was determined at three different ambient temperatures in air and in an equivalent helium-oxygen mixture. It was found that when the ambient temperature is near the skin temperature of the rat, the effect of helium is insignificant. If the ambient temperature is lowered, helium induces an increased metabolism over air at the same temperature. Since helium has a thermal conductivity about six times greater than nitrogen, it is concluded that the accelerated metabolism is in response to the greater heat loss in the presence of helium and the magnitude of this response is proportional to the thermal gradient between the animal and the environment.


1971 ◽  
Vol 13 (2) ◽  
pp. 303-313 ◽  
Author(s):  
D. B. Stephens

SUMMARY1. The metabolic rates of 58 individual piglets kept either on a straw or on a concrete floor at ambient temperatures near to 10°, 20° or 30°C have been measured with ages ranging from newborn to 9 days, and body weight from 1·0 to 3·2 kg. The oxygen consumption was measured on each floor material at the chosen ambient temperature thus allowing paired comparisons for each animal.2. In comparison with the concrete floor, oxygen consumption on straw was reduced by 18% at 10°C, 27% at 20°C and by 12% at 30°C for pigs 2 to 9 days old. The regression coefficients of mean log (oxygen consumption) on log (body weight) were around 0·66 at 10° and 20°C. At 30°C the value was 0·99 ± 0·14. The regression coefficients were not significantly affected by the presence of a straw floor showing that its effect did not vary with body weight. Corresponding values foi piglets below 24 hours of age were 17% at 10°C, 27% at 20°C and 22% at 30°C ambient temperature.3. Moving a piglet on to a straw floor at 10°C had the same thermal effect as raising the ambient temperature to 18°C. Similar treatment at 30°C was equivalent to raising the ambient temperature to 32°C.4. Lowering ambient temperature to increase the temperature gradient between the homeothermic body of the piglet and the environment progressively increased heat loss in all cases. There was a concomitant decrease in the calculated conductance between core and environment which was more pronounced for the piglets lying on the concrete floor.


1965 ◽  
Vol 20 (3) ◽  
pp. 405-410 ◽  
Author(s):  
Hermann Pohl

Characteristics of cold acclimation in the golden hamster, Mesocricetus auratus, were 1) higher metabolic rate at -30 C, 2) less shivering when related to ambient temperature or oxygen consumption, and 3) higher differences in body temperature between cardiac area and thoracic subcutaneous tissues at all ambient temperatures tested, indicating changes in tissue insulation. Cold-acclimated hamsters also showed a rise in temperature of the cardiac area when ambient temperature was below 15 C. Changes in heat distribution in cold-acclimated hamsters suggest higher blood flow and heat production in the thoracic part of the body in the cold. The thermal conductance through the thoracic and lumbar muscle areas, however, did not change notably with lowering ambient temperature. Marked differences in thermoregulatory response to cold after cold acclimation were found between two species, the golden hamster and the thirteen-lined ground squirrel, showing greater ability to regulate body temperature in the cold in hamsters. hibernator; oxygen consumption— heat production; body temperature — heat conductance; muscular activity — shivering; thermoregulation Submitted on July 6, 1964


2010 ◽  
Vol 37 (9) ◽  
pp. 870 ◽  
Author(s):  
Roger S. Seymour ◽  
Ilse Silberbauer-Gottsberger ◽  
Gerhard Gottsberger

The roles of floral thermogenesis in pollination biology include attraction and reward of insects. Magnolia ovata (A.St.-Hil.) Spreng. produces ~56 g, bisexual, protogynous and scented flowers. Two distinct episodes of thermogenesis occur during anthesis: one beginning at about sunset and lasting ~3 h in the female phase and another that occurs synchronously 24 h later and lasting 4 h in the male phase. Female stage flowers produce up to 0.36 W to reach 27.3°C, which is 3.9°C above ambient air. In the male stage, corresponding values are 0.79 W, 29.7°C and 5.4°C, respectively. Most heat is generated in the petals in both phases (74 and 65%). Maximum, mass-specific rate of respiration is 23 nmol s–1 g–1 in the petals and 100 nmol s–1 g–1 in the anthers. The flowers are apparently not thermoregulatory, because respiration rate decreases, rather than increases, with decreasing ambient temperature. Scarab beetles, Cyclocephala literata, enter the floral chamber created by the petals in the female phase, mate, consume floral parts (mainly petals) and then depart in the male phase. Temperatures maintained in the floral chamber are sufficient to provide beetles with significant energy savings during their activities in both phases. Thermogenesis is, therefore, consistent with volatilisation of floral fragrances and energy rewards to beetle visitors.


2008 ◽  
Vol 86 (3) ◽  
pp. 161-169 ◽  
Author(s):  
Kenneth C. Welch, ◽  
Raul K. Suarez

During migratory stopovers, rufous hummingbirds ( Selasphorus rufus (Gmelin, 1788)) can achieve high daily rates of net energy intake and mass gain while foraging at a range of elevations and ambient temperatures, despite the high energetic costs of hovering flight and thermoregulation. To gain insights into the factors affecting the energetic costs incurred during foraging, we captured migratory hummingbirds and measured their oxygen consumption rates during hover-feeding. Measurements were performed in situ where rufous hummingbirds forage as they migrate at several locations along a gradient in elevation and over the range of ambient temperatures normally experienced. Oxygen consumption rates during hover-feeding varied between the sexes and between juveniles and adults. These differences appeared to reflect differences in the power requirements for hovering flight in relation to variation in wing morphology. Decreasing ambient temperature and increasing elevation both significantly increased oxygen consumption rate during hover-feeding. The effects of these two environmental variables were additive, suggesting that hummingbird thermoregulatory requirements were not met by the additional heat produced by the higher metabolic rate necessary to support hovering flight at higher elevation. These results provide insight into the ways different foraging strategies may allow hummingbirds to maximize net energy intake.


PEDIATRICS ◽  
1964 ◽  
Vol 33 (4) ◽  
pp. 487-495
Author(s):  
Forrest H. Adams ◽  
Tetsuro Fujiwara ◽  
Robert Spears ◽  
Joan Hodgman

Sixteen serial observations of oxygen consumption, carbon dioxide production, R.Q., respiratory rate, rectal temperature, and skin blood flow were made on six premature infants ranging in age from 3 hours to 12 days and weighing from 1.14 to 1.94 kg, utilizing a specially designed climatized chamber at neutral (32-34°C), low (21-23°C), and high (36-38°C) ambient temperatures. Ten premature infants ranging in age from 2½ hours to 18 days were studied at high (36-38°C) ambient temperature. At low ambient temperature, there was a mean increase of 63% in oxygen consumption even in infants under 24 hours of age. At the end of the rewarming period, rectal temperature, which had been lowered during a 20-minute exposure to 21-23°C, nearly recovered to the original level in infants in both of the age groups of 0 to 24 hours and 2 to 5 days, whereas in the 6 to 12 day old group, it returned faster than the former two and it was increased by 0.32 to 1.9°C (mean 0.9°C). At 36-38°C, ambient temperature, the mean oxygen consumption increased 18% in infants ages 2½ to 7½ hours, whereas there was no significant increase in infants ages 10 to 18 days. Sweating and significant vasodilatation generally did not occur even in the older infants. The respiratory rate was increased in most infants. It is suggested that heat loss through the respiratory tract might be important to the premature infant who has a lack of evaporative means at high ambient temperature.


1986 ◽  
Vol 34 (1) ◽  
pp. 25 ◽  
Author(s):  
JR Roberts ◽  
RV Baudinette

Stubble quail occur in more arid areas of Australia than king quail; however, the rates of metabolism and the ability to regulate body temperature in response to varying ambient temperature are similar in both birds, and resemble those of other quail species. At high ambient temperatures, rates of heat loss mediated by evaporative water loss are lower than those previously reported for more xerophilic species. Overall rates of water turnover and evaporative water loss at lower ambient temperatures are at the lower end of the range predicted for birds.


2020 ◽  
Vol 7 (4) ◽  
pp. 191989
Author(s):  
Paul J. Schaeffer ◽  
M. Teague O'Mara ◽  
Japhet Breiholz ◽  
Lara Keicher ◽  
Javier Lázaro ◽  
...  

Small endothermic mammals have high metabolisms, particularly at cold temperatures. In the light of this, some species have evolved a seemingly illogical strategy: they reduce the size of the brain and several organs to become even smaller in winter. To test how this morphological strategy affects energy consumption across seasonally shifting ambient temperatures, we measured oxygen consumption and behaviour in the three seasonal phenotypes of the common shrew ( Sorex araneus ), which differ in size by about 20%. Body mass was the main driver of oxygen consumption, not the reduction of metabolically expensive brain mass. Against our expectations, we found no change in relative oxygen consumption with low ambient temperature. Thus, smaller body size in winter resulted in significant absolute energy savings. This finding could only partly be explained by an increase of lower cost behaviours in the activity budgets. Our findings highlight that these shrews manage to avoid one of the most fundamental and intuitive rules of ecology, allowing them to subsist with lower resource availability and successfully survive the harsh conditions of winter.


1975 ◽  
Vol 53 (2) ◽  
pp. 293-298 ◽  
Author(s):  
Peter B. Raven ◽  
James E. Wilkerson ◽  
Steven M. Horvath ◽  
Nils W. Bolduan

The metabolic, thermal, and cardiovascular responses of two male Caucasians to a 2 h exposure to ambient temperatures ranging between 28 °C and 5 °C were studied and related to the respective ambient temperatures. The metabolic heat production increased linearly with decreasing ambient temperature, where heat production (kcal∙m−2∙h−1) = −2.79 Ta °C + 103.4, r = −0.97, P < 0.001. During all exposures below 28 °C, the rate of decrease in mean skin temperature [Formula: see text] was found to be an exponential function dependent upon the ambient temperature (Ta) and the time of exposure. Reestablishment of [Formula: see text] steady state occurred at 90–120 min of exposure, and the time needed to attain steady state was linearly related to decreasing Ta. The net result was that a constant ratio of 1.5 of the external thermal gradient to the internal thermal gradient was obtained, and at all experimental temperatures, the whole body heat transfer coefficient remained constant. Cardiac output was inversely related to decreasing Ta, where cardiac output [Formula: see text], r = −0.92, P < 0.01. However, the primary reason for the increased [Formula: see text], the stroke output, was also described as a third-order polynomial, although the increasing stroke volume throughout the Ta range (28–5 °C) was linearly related to decreasing ambients. The nonlinear response of this parameter which occurred at 20 °C ≥ Ta ≥ 10 °C suggested that the organism's cardiac output response was an integration of the depressed heart rate response and the increasing stroke output at these temperatures.


1978 ◽  
Vol 90 (3) ◽  
pp. 605-609 ◽  
Author(s):  
M. Van Kampen ◽  
B. W. Mitchell ◽  
H. S. Siegel

SummarySeven-week-old White Rock males were exposed to step-wise increases in ambient temperatures from 7·7 to 37·7 °C in light and dark environments. Heart rate decreased with increasing ambient temperature with a quadratic slope (P ≤ 0·0001). Heart rate was lower during the dark period than during the light period (P ≤ 0·06). There was a positive linear correlation between heart rate and oxygen consumption (γ = 0·997) for ambient temperatures from 7·7 to 37·7 °C.Body temperatures began to increase significantly when ambient temperature reached beyond 27·5 °C. The increases followed a quadratic slope (P ≤ 0·0001). Body temperatures during the light period were significantly higher than during the dark period (P ≤ 0·05).


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