Energy budget in free-living animals: a novel approach based on the doubly labeled water method

1997 ◽  
Vol 272 (4) ◽  
pp. R1336-R1343 ◽  
Author(s):  
M. Kam ◽  
A. A. Degen

We provide a theoretical and practical model for the calculation of energy balance of free-living animals using the doubly labeled water method. Energy expenditure, metabolizable energy intake, and body energy balance (energy retention, negative or positive) of animals are estimated using CO2 production, water influx, and dietary habits. This model accounts for CO2 produced from the 1) oxidation of dietary substrates, 2) catabolism of body tissue, and 3) deposition of body energy. We examined the model using data from studies on five homeotherms reported in the literature. The ratios between daily energy expenditure using our model and that presented in the reports ranged between 0.76 and 1.18. Metabolizable energy intakes were as low as 43% of energy expenditure in negative energy-balanced hummingbirds and as high as 245% of energy expenditure in positive energy-balanced koala bears. This model is the first that allows theoretical calculation of all energy budget components, including energy retention, in free-living animals using the doubly labeled water method.

1989 ◽  
Vol 67 (1) ◽  
pp. 14-18 ◽  
Author(s):  
C. H. Forbes-Ewan ◽  
B. L. Morrissey ◽  
G. C. Gregg ◽  
D. R. Waters

The doubly labeled water method was used to estimate the energy expended by four members of an Australian Army platoon (34 soldiers) engaged in training for jungle warfare. Each subject received an oral isotope dose sufficient to raise isotope levels by 200–250 (18O) and 100–120 ppm (2H). The experimental period was 7 days. Concurrently, a factorial estimate of the energy expenditure of the platoon was conducted. Also, a food intake-energy balance study was conducted for the platoon. Mean daily energy expenditure by the doubly labeled water method was 4,750 kcal (range 4,152–5,394 kcal). The factorial estimate of mean daily energy expenditure was 4,535 kcal. Because of inherent inaccuracies in the food intake-energy balance technique, we were able to conclude only that energy expenditure, as measured by this method, was greater than the estimated mean daily intake of 4,040 kcal. The doubly labeled water technique was well tolerated, is noninvasive, and appears to be suitable in a wide range of field applications.


1990 ◽  
Vol 63 (2) ◽  
pp. 165-175 ◽  
Author(s):  
J. F. Aguilera ◽  
C. Prieto ◽  
J. FonollÁ

Twelve goats of the Granadina breed in mid- and late lactation were used in two consecutive years to determine their protein and energy requirements for lactation. The animals were individually fed on diets based on pelleted lucerne (Medicago sativa) hay and barley. A total of six balance experiments were carried out. Gas exchange was measured using open-circuit respiration chambers. Milk yield ranged widely from 0.649 to 1.742 kg/d in the first year and from 0.222 to 1.989 kg/d in the second year, a steady decline in milk output being observed as lactation progressed. Milk composition remained rather constant during the midstage of lactation, with an average content (/kg milk) for total solids, total nitrogen, fat and gross energy of 149.7 g, 5.39 g, 58.8 g and 3.59 MJ respectively. Total endogenous N, endogenous urinary N and maintenance requirement for N in lactating goats were estimated to be 244, 218 mg N/kg body-weight (W)0.75 per d and 478 mg total N/kg W0.75 per d respectively from regression equations. A constant efficiency of use of dietary N for milk N plus retained N of 51.0 % was found. By regressing milk energy plus apparent body energy retention or loss on metabolizable energy (ME) intake, the maintenance energy requirement was estimated to be 401 kJ ME/kg W0.79 per d. When estimating the corrected milk yield as milk energy +(0.84 x negative energy retention) +(1.05 x positive energy retention), regression analysis indicated that the overall efficiency of use of ME for lactation was 66.7%. Also, from a plot of apparent body energy retention v milk energy yield, both expressed as a percentage of ME intake above maintenance, the efficiency with which ME was used to promote energy retention in the body during lactation was calculated to be 0.907 times that for milk secretion.


2014 ◽  
Vol 8 (3) ◽  
pp. 241 ◽  
Author(s):  
Jonghoon Park ◽  
Ishikawa-Takata Kazuko ◽  
Eunkyung Kim ◽  
Jeonghyun Kim ◽  
Jinsook Yoon

1989 ◽  
Vol 67 (10) ◽  
pp. 1190-1198 ◽  
Author(s):  
S. B. Roberts

The basis of the doubly labeled water method is measurement of the differential rates of disappearance of two isotopes of water (H218O and either 2H2O or 3H2O, administered at the start of the study) from body water. Published studies indicate that, in its current forms, this technique can be used to provide accurate and reasonably precise information on carbon dioxide production, total body water, and water intake in free-living humans and many small animals. Total energy expenditure can be calculated from carbon dioxide production with little loss of precision. Metabolizable energy intake can also be predicted, as the sum of total energy expenditure plus an estimate for the change in body energy stores during the measurement, but this prediction is unlikely to be accurate and precise unless the subject is in approximate energy balance.Key words: doubly labeled water, energy metabolism, energy expenditure, water intake, body composition.


1974 ◽  
Vol 19 (2) ◽  
pp. 127-139 ◽  
Author(s):  
A. J. F. Webster ◽  
J. M. Brockway ◽  
J. S. Smith

SUMMARY1. According to the Agricultural Research Council (1965) energy retention in cattle is predicted from metabolizable energy (ME) intake, the net availabilities of ME for maintenance (km) and for fattening (kf) and measurements made of fasting metabolism (F). The present experiments were designed to examine the validity of the use of F as a basis from which to predict energy retention.2. Four British Friesian and four Aberdeen Angus steers were fed, from weaning to slaughter at about 450 kg, a barley-based, pelleted diet at two levels calculated to yield overall efficiencies of retention of ME of 20% and 10% respectively. Successive measurements were made of the energy balance of each animal at intervals of 4 to 8 weeks.3. The metabolizability of the diet was measured for both sheep and cattle. In both species metabolizability was greater at the higher level of feeding. In sheep kf measured directly or estimated from metabolizability was 0·61.4. Measured values for F in cattle agreed closely with values given by the Agricultural Research Council.5. Basal metabolism in the growing animal (F') was predicted by extrapolation to zero intake of measurements made on animals in positive energy balance. Log F' during growth was proportional to log body weight0·73. Expressed in terms of the usual exponent of metabolic body size, F' was about 440 kJ/kg0·75 per 24 hr throughout growth. There were no major differences in F' attributable to breed or to level of food intake.6. The results indicate that F is not a good basis from which to predict energy retention in steers.


1994 ◽  
Vol 124 (suppl_12) ◽  
pp. 2594S-2600S ◽  
Author(s):  
O. Ballevre ◽  
G. Anantharaman-Barr ◽  
P. Gicquello ◽  
C. Piguet-Welsh ◽  
A.-L. Thielin ◽  
...  

1991 ◽  
Vol 261 (3) ◽  
pp. E402-E409 ◽  
Author(s):  
E. Ravussin ◽  
I. T. Harper ◽  
R. Rising ◽  
C. Bogardus

The doubly labeled water (2H2(18)O) method to assess energy expenditure in free-living conditions has been successfully validated against gas exchange measurements in lean healthy volunteers in both sedentary conditions and during sustained heavy exercise. However, no data are available on obese subjects. We therefore compared the 2H2(18)O method with indirect calorimetry (respiratory chamber) in 12 male subjects covering a wide range of body weight and composition (61-190 kg, 7-41% fat). Isotope pool sizes and elimination rates were calculated from 18O and 2H enrichments in baseline urine samples and in 7-h, 11.5-h, and daily postdose urine samples using the multipoint slope/intercept method. Results were corrected for isotopic fractionation. Mean 7-day energy expenditure in the respiratory chamber varied from 1,851 to 4,105 kcal/day. The doubly labeled water method tended to underestimate energy expenditure (-2.5 +/- 5.8%, not equal to 0, range -14 to +4%), with the larger underestimate observed in heavier and fatter subjects (r = -0.82 and -0.68, P less than 0.02, respectively). The underestimation in heavier subjects might be related to larger sequestration of deuterium during fat synthesis. In conclusion, the doubly labeled water method is a suitable and accurate method to measure energy expenditure in free-living conditions but might provide a slightly underestimated figure in fatter subjects.


1989 ◽  
Vol 66 (2) ◽  
pp. 644-652 ◽  
Author(s):  
J. Seale ◽  
C. Miles ◽  
C. E. Bodwell

Attempts to estimate human energy expenditure by use of doubly labeled water have produced three methods currently used for calculating carbon dioxide production from isotope disappearance data: 1) the two-point method, 2) the regression method, and 3) the integration method. An ideal data set was used to determine the error produced in the calculated energy expenditure for each method when specific variables were perturbed. The analysis indicates that some of the calculation methods are more susceptible to perturbations in certain variables than others. Results from an experiment on one adult human subject are used to illustrate the potential for error in actual data. Samples of second void urine, 24-h urine, and breath collected every other day for 21 days are used to calculate the average daily energy expenditure by three calculation methods. The difference between calculated energy expenditure and metabolizable energy on a weight-maintenance diet is used to estimate the error associated with the doubly labeled water method.


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