scholarly journals Can the Basal Metabolic Rate of Endotherms Be Explained by Biophysical Modeling? Response to “A New Model for the Body Size–Metabolism Relationship”

2011 ◽  
Vol 84 (1) ◽  
pp. 107-110 ◽  
Author(s):  
Roger S. Seymour ◽  
Craig R. White
Keyword(s):  
Body Size ◽  
Metabolic Rate ◽  
Basal Metabolic Rate ◽  
The Body ◽  
Biophysical Modeling ◽  
New Model

Respiratory Exchange and Body Size in the Aldabra Giant Tortoise

1971 ◽  
Vol 55 (3) ◽  
pp. 651-665 ◽  
Author(s):  
G. M. HUGHES ◽  
R. GAYMER ◽  
MARGARET MOORE ◽  
A. J. WOAKES
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Metabolic Rate ◽  
Relative Proportion ◽  
The Body ◽  
O2 Consumption ◽  
Weight Range ◽  
Testudo Hermanni ◽  
The Mean ◽  
Good Agreement

1. The O2 consumption and CO2 release of nine giant tortoises Testudo gigantea (weight range 118 g-35·5 kg) were measured at a temperature of about 25·5°C. Four European tortoises Testudo hermanni (weight range 640 g-2·16 kg) were also used. The mean RQ values obtained were 1·01 for T. gigantea and 0·97 for T. hermanni. These values were not influenced by activity or size. 2. The data was analysed by plotting log/log regression lines relating body weight to O2 consumption. Both maximum and minimum metabolic rates recorded for each individual T. gigantea showed a negative correlation with body weight. For active rates the relation was O2 consumption = 140·8W0·97, whereas for inactive animals O2 consumption = 45·47W0·82. 3. The maximum rates were obtained from animals that were observed to be active in the respirometer and the minimum rates from animals that remained quiet throughout. The scope for activity increased with body size, being 82 ml/kg/h for animals of 100 g and 103 ml/kg/h for 100 kg animals. The corresponding ratio between maximum and minimum rates increases from about 2 to 6 for the same weight range. 4. Values for metabolic rate in T. hermanni seem to be rather lower than in T. gigantea. Analysis of the relative proportion of the shell and other organs indicates that the shell forms about 31% of the body weight in adult T. hermanni but only about 18% in T. gigantea of similar size. The shell is not appreciably heavier in adult T. gigantea (about 20%). 5. Data obtained for inactive animals is in good agreement with results of other workers using lizards and snakes. Previous evidence suggesting that chelonians show no reduction in metabolic rate with increasing size is not considered to conflict with data obtained in the present work.

Body-size scaling of metabolic rate in the trilobite Eldredgeops rana

Paleobiology ◽  
2013 ◽  
Vol 39 (1) ◽  
pp. 109-122 ◽  
Author(s):  
Douglas S. Glazier ◽  
Matthew G. Powell ◽  
Travis J. Deptola
Keyword(s):  
Body Size ◽  
Metabolic Rate ◽  
Cell Size ◽  
The Body ◽  
Cell Multiplication ◽  
Compound Eyes ◽  
Metabolic Scaling ◽  
Size Scaling ◽  
Size Model ◽  
Facet Size

We infer the body-size scaling slope of metabolic rate in a trilobite by applying a cell-size model that has been proposed to explain metabolic scaling in living organisms. This application is especially tractable in fossil arthropods with well-preserved compound eyes because the number and size of eye facets appear to be useful proxies for the relative number and size of cells in the body. As a case study, we examined the ontogenetic scaling of facet size and number in a ∼390-Myr-old local assemblage of the trilobite Eldredgeops rana, which has well-preserved compound eyes and a wide body-size range. Growth in total eye lens area resulted from increases in both facet area and number in relatively small (presumably young) specimens, but only from increases in facet area in large (presumably more mature) specimens. These results suggest that early growth in E. rana involved both cell multiplication and enlargement, whereas later growth involved only cell enlargement. If the cell-size model is correct, then metabolic rate scaled allometrically in E. rana, and the scaling slope of log metabolic rate versus log body mass decreased from ∼0.85 to 0.63 as these animals grew. This inferred age-specific change in metabolic scaling is consistent with similar changes frequently observed in living animals. Additional preliminary analyses of literature data on other trilobites also suggest that the metabolic scaling slope was <1 in benthic species, but ∼1 in pelagic species, as has also been observed in living invertebrates. The eye-facet size (EFS) method featured here opens up new possibilities for examining the bioenergetic allometry of extinct arthropods.

Age Changes in Body Size, Body Composition and Basal Metabolism

1956 ◽  
Vol 186 (2) ◽  
pp. 207-210 ◽  
Author(s):  
M. C. Conrad ◽  
A. T. Miller
Keyword(s):  
Body Composition ◽  
Body Size ◽  
Metabolic Rate ◽  
Relative Weight ◽  
Extracellular Fluid ◽  
The Body ◽  
Basal Metabolism ◽  
Albino Rats ◽  
Tissue Mass ◽  
Bone Minerals

The interrelations of body size, body composition and basal metabolism were studied in 69 albino rats ranging in age from 18–174 days. The decline in metabolic rate with age was more rapid than would be predicted from the weight0.75 rule which eliminates the influence of body size in interspecific measurements. Body composition analyses indicated that the increase with age in metabolically inert fat and bone minerals was approximately balanced by a corresponding decrease in metabolically inert extracellular fluid, so that ‘active tissue mass’ was virtually unchanged. Calculations based on data in the literature indicate that about one-half the decline in metabolic rate with age may be due to the corresponding decrease in the relative weight of the viscera. The remainder of the decline in metabolic rate must be due to factors other than changes in the chemical or histological composition of the body.

scholarly journals Incubation temperature and physiological aging in the zebra finch

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0260037
Author(s):  
Henrik H. Berntsen ◽  
Claus Bech
Keyword(s):  
Body Size ◽  
Oxidative Damage ◽  
Metabolic Rate ◽  
Body Mass ◽  
Basal Metabolic Rate ◽  
Incubation Temperature ◽  
Phenotypic Variability ◽  
Body Growth ◽  
Optimal Incubation

In birds, incubation temperature has received increased attention as an important source of phenotypic variability in offspring. A lower than optimal incubation temperature may negatively affect aspects of nestling physiology, such as body growth and energy metabolism. However, the long-term effects of sub-optimal incubation temperature on morphology and physiology are not well understood. In a previous study, we showed that zebra finches from eggs incubated at a low temperature (35.9°C) for 2/3 of the total incubation time suffered a lower post-fledging survival compared to individuals that had been incubated at higher temperatures (37.0 and 37.9°C). In the present study, we investigated whether these variations in incubation temperature could cause permanent long-lasting differences in body mass, body size, or basal metabolic rate. Furthermore, we tested whether the observed differences in survival between treatment groups would be reflected in the rate of physiological deterioration, assessed through oxidative damage and decreased metabolic rate with age (i.e. ‘metabolic aging’). Incubation temperature did not significantly affect embryonic or nestling body growth and did not influence final adult body mass or body size. Nor was there any long-term effect on basal metabolic rate. Birds from eggs incubated at the lowest temperature experienced an accumulation of oxidative damage with age, although this was not accompanied by an accelerated rate of metabolic aging. The present results suggest that the low survival in these birds was possibly mediated by increased oxidative stress, but independent of body growth and the basal metabolic rate.

Observations of the basal metabolic rate in cardiovascular insufficiency

1937 ◽  
Vol 33 (7) ◽  
pp. 817-824
Author(s):  
E. B. Segen ◽  
K. I. Bogovarov
Keyword(s):  
Metabolic Rate ◽  
Basal Metabolic Rate ◽  
Blood Circulation ◽  
Minute Volume ◽  
The Body ◽  
Circulatory Failure ◽  
Circulatory Disorders

The question of the regulation of blood circulation is currently still not clear enough, but it is known that circulatory disorders are associated with changes both in protoplasmodynamics and in the hemodynamics of the body. Recently, there have been significant advances in the study of hemodynamics in circulatory failure. Much attention in these studies is paid to the issue of changes in the value of the minute volume of the heart.

Basal metabolic rate and body composition at high altitudes

1961 ◽  
Vol 16 (3) ◽  
pp. 431-434 ◽  
Author(s):  
E. Picó;n-Reátegui
Keyword(s):  
Body Composition ◽  
Metabolic Rate ◽  
High Altitude ◽  
Sea Level ◽  
Basal Metabolic Rate ◽  
Technical Assistance ◽  
Cell Mass ◽  
The United States ◽  
The Body ◽  
Adult Males

Basal metabolic rate (BMR) and body composition were determined in 17 healthy adult males living at an altitude of 14,900 ft above sea level. Using body surface area as a standard of reference and following the criterion of Boothby et al. ( Am. J. Physiol. 116: 468, 1936), the BMR of the high-altitude resident fell within the limits considered normal for healthy adults at sea level. A comparison with the data obtained by investigators in the United States and in India shows that, when either fat-free body mass (FFM), cell mass (C), or cell solids (S) are the standard of reference, the BMR is higher in the high-altitude resident. The higher O2 consumption per kilogram of FFM, C, or S in the high-altitude resident seems to be one of the many mechanisms developed by the body in its process of adaptation to the low O2 tension. Note: (With the Technical Assistance of Melquiades Huayna-Vera) Submitted on October 24, 1960

Thyroid Function and Obesity: From Mechanisms to the Benefits of Levothyroxine in Obese Patient

2021 ◽  
Vol 21 ◽  
Author(s):  
Vincenzo De Geronimo ◽  
Rossella Cannarella ◽  
Sandro La Vignera
Keyword(s):  
Energy Expenditure ◽  
Metabolic Rate ◽  
Basal Metabolic Rate ◽  
Hormone Receptors ◽  
Uncoupling Protein ◽  
Resting Energy Expenditure ◽  
The Body ◽  
Expenditure Rate ◽  
Basal Energy Expenditure ◽  
Clinical Conditions

Background: Thyroid disease and obesity are very common clinical conditions in the general population. They can occur together in the same subject, but their relationship does not seem to be exclusively stochastic. Aim: We critically reviewed the evidence of the literature in the attempt to provide explanation for this association, in order to understand the possible benefits of levothyroxine therapy in euthyroid obese patients. Results: A low energy expenditure rate can lead to obesity. Maintaining Basal Metabolic Rate (BMR) is the main cause of energy expenditure for the body, which is regulated by thermogenesis. Thyroid hormone receptors (TR) play different roles in the induction of thermogenetic mechanisms: TRα is fundamental to induce thermogenesis, TRβ triggers the expression of uncoupling protein 1(UCP1). Despite such mechanisms, there is not currently evidence to treat subjects suffering from obesity with thyroid hormones. Conclusion: Replacement therapy should be reserved to patients with obvious signs of subclinical or clinical hypothyroidism. Definitions: Basal metabolic rate (BMR) or basal energy expenditure (BEE): measurement obtained under total inactivity and controlled research conditions; resting energy expenditure (REE): measurement obtained when an individual is sitting quietly (is mildly higher than BMR/BEE).

METABOLIC RATE AND ITS TEMPERATURE-ADAPTIVE SIGNIFICANCE IN SIX GEOGRAPHIC RACES OF PEROMYSCUS

1965 ◽  
Vol 43 (2) ◽  
pp. 309-323 ◽  
Author(s):  
J. S. Hayward
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Metabolic Rate ◽  
Single Equation ◽  
Adaptive Significance ◽  
The Body ◽  
Single Group ◽  
Critical Temperatures ◽  
Wide Range ◽  
Per Se

The metabolic rate characteristics of six races of Peromyscus, selected from a wide range of habitats, have been determined over the temperature range 0° to 35 °C. After acclimation to standardized laboratory conditions, critical temperatures and metabolic responses to temperatures below thermoneutrality were largely a function of body size: the larger the mouse, the greater its thermoregulatory efficiency. Body size per se is not correlated with the gross climate of the respective habitats. A single equation which predicts the metabolic rate of these races at any temperature between 0° and 27 °C, from a knowledge of body weight and body temperature, is derived.When considered as a single group, the basal oxygen consumption of all races varied with body weight0,60 over the body weight range of 14.7 to 36.0 g and was insignificantly different from the accepted interspecies approximation. The basal metabolic rates of each race showed no temperature-adaptive differences, especially when considered in relation to body composition. It is concluded that basal metabolic rate is nonadaptive to climate in these races of Peromyscus and consequently has played no important part in their distribution and speciation.

scholarly journals Scaling of the Mammalian Brain: the Maternal Energy Hypothesis

Physiology ◽  
1996 ◽  
Vol 11 (4) ◽  
pp. 149-156 ◽  
Author(s):  
RD Martin
Keyword(s):  
Body Size ◽  
Metabolic Rate ◽  
Basal Metabolic Rate ◽  
Brain Size ◽  
Developing Brain ◽  
Correlation Network ◽  
Gestation Period ◽  
Mammalian Brain ◽  
Metabolic Capacity ◽  
Simple Scaling

Mammalian brain sizes have been linked to specific behavioral or physiological features because of simple scaling correlations. Examination of the correlation network for body size, brain size, basal metabolic rate, and gestation period indicates that the primary link is between maternal metabolic capacity and the developing brain of the offspring.

Sign in / Sign up

Export Citation Format

Share Document