scholarly journals On the Interplay among Ambient Temperature, Basal Metabolic Rate, and Body Mass

2018 ◽  
Vol 192 (4) ◽  
pp. 518-524 ◽  
Author(s):  
Daniel E. Naya ◽  
Hugo Naya ◽  
Craig R. White
1990 ◽  
Vol 151 (1) ◽  
pp. 349-359 ◽  
Author(s):  
F. Geiser ◽  
R. V. Baudinette

1. Rewarming rate from torpor and body mass were inversely related in 86 mammals ranging in body mass between 2 and 8500 g. 2. Most of the mammalian taxa investigated showed a similar change of rewarming rate with body mass. Only the insectivores showed a more pronounced increase in rewarming with a decrease in body mass than did the other taxa. The rates of rewarming of marsupials were similar to those of placentals. 3. At low air temperature (Ta), the rate of rewarming of marsupials was not related to body mass, although a strong relationship between the two variables was observed in the same species at high Ta. 4. The slopes relating rewarming rates and body mass of the mammalian groups and taxa analysed here were similar to those obtained earlier for mass-specific basal metabolic rate (BMR) and body mass in mammals, suggesting that the rate of rewarming and BMR are physiologically linked.


1994 ◽  
Vol 72 (11) ◽  
pp. 1967-1972 ◽  
Author(s):  
Donald W. Thomas ◽  
Kathy Martin ◽  
Hélène Lapierre

We measured background 2H and 18O abundances and field metabolic rate (FMR) for White-tailed Ptarmigan (Lagopus leucurus) above 3600 m elevation in the Colorado Rocky Mountains between May and July. 18O abundances ranged from 1982.4 to 2018.6 ppm [Formula: see text], while 2H abundance ranged from 142.8 to 154.0 ppm [Formula: see text]. Mean 2H abundance followed closely (−0.3 ppm deviation) the level predicted by Tatner's empirical model relating 2H and ambient temperature. However, 18O was more enriched than predicted (+3.4 ppm), which may reflect 18O fractionation in the plant diet. FMR, measured by means of the doubly labelled water method, ranged from 206.4 to 442.7 kJ/d and was not related to body mass. However, for males, FMR was significantly and positively related to age. Because of high variation in background isotope levels, the use of mean 2H and 18O background abundances instead of individual backgrounds would introduce a mean error of 7.1% (range −8.9 to +11.4%) in calculations of CO2 production and FMR.


1992 ◽  
Vol 83 (3) ◽  
pp. 325-330 ◽  
Author(s):  
Franco Salomon ◽  
Ross C. Cuneo ◽  
Richard Hesp ◽  
Jenny F. Morris ◽  
Lucilla Poston ◽  
...  

1. The relationship of lean body mass, plasma insulin concentration and leucocyte active sodium transport with basal metabolic rate was investigated in 24 adults with growth hormone deficiency before and after treatment with recombinant human growth hormone and in 10 patients with untreated acromegaly. 2. Based on total-body potassium determined by whole-body 40K counting, patients with acromegaly had increased lean body mass, whereas lack of growth hormone was associated with decreased lean body mass. 3. By indirect calorimetry, patients with acromegaly had increased basal metabolic rates and patients with growth hormone deficiency had decreased values when expressed as percentages of values predicted from the WHO/FAO/UNU equations. Basal metabolic rate expressed in terms of lean body mass was similar in acromegaly and growth hormone deficiency, but was higher than normal in both patient groups. 4. The leucocyte ouabain-sensitive sodium efflux rate constant was decreased in both patients with acromegaly and patients with growth hormone deficiency, and there was no correlation with basal energy expenditure, fasting plasma insulin level or serum growth hormone level. 5. There was no increase in the sodium efflux rate constant in patients with growth hormone deficiency after 1 month on treatment with recombinant human growth hormone. 6. Apparent differences in basal metabolic rate in growth hormone deficiency and acromegaly are due to changes in lean body mass. Both adults with growth hormone deficiency and patients with acromegaly have increased energy expenditure, probably owing to changes in fuel metabolism which are not reflected in the leucocyte sodium pump activity.


2019 ◽  
Author(s):  
Michael Briga ◽  
Simon Verhulst

AbstractCrucial to our understanding of the ageing process is identifying how traits change with age, which variables alter their ageing process and whether these traits associate with lifespan.We here investigated metabolic ageing in zebra finches. We longitudinally monitored 407 individuals during six years and collected 3213 measurements of two independent mass-adjusted metabolic traits: basal metabolic rate (BMRm) at thermoneutral temperatures and standard metabolic rate (SMRm), which is the same as BMRm but at ambient temperatures below thermoneutrality.BMRmdecreased linearly with age, consistent with earlier reports. In contrast, SMRmincreased linearly with age. To the best of our knowledge, this is the first quantification of SMRm ageing, and thereby of the contrast between SMRm and BMRm ageing.Neither metabolic rate nor metabolic ageing rate were associated with individual lifespan. Moreover, experimental manipulations of environmental quality that decreased BMRm and SMRm and shortened lifespan with 6 months (12%) did not affect the ageing of either metabolic trait. Females lived 2 months (4%) shorter than males, but none of the metabolic traits showed sex-specific differences at any age.Our finding that ageing patterns of metabolic rate vary depending on the ambient temperature illustrates the importance of studying ageing in an ecologically realistic setting.Our results add to the mounting evidence that within an organism ageing is an asynchronous process.


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