scholarly journals Energy Expenditure and Water Flux of Rüppell’s Foxes in Saudi Arabia

2002 ◽  
Vol 75 (5) ◽  
pp. 479-488 ◽  
Author(s):  
Joseph B. Williams ◽  
Danny Lenain ◽  
Stephane Ostrowski ◽  
B. I. Tieleman ◽  
Philip J. Seddon
Keyword(s):  
Saudi Arabia ◽  
Energy Expenditure ◽  
Water Flux

Flux hydriques et métabolisme énergétique dans un peuplement de Lacertidés des îles Kerkennah (Tunisie)

1988 ◽  
Vol 66 (3) ◽  
pp. 555-561 ◽  
Author(s):  
Roland Vernet ◽  
Claude Grenot ◽  
Saïd Nouira
Keyword(s):  
Energy Expenditure ◽  
Daily Activity ◽  
Water Flux ◽  
Sympatric Species ◽  
Doubly Labeled Water ◽  
Daily Energy Expenditure ◽  
Water Turnover ◽  
Semiarid Environment ◽  
Daily Energy ◽  
Active Forager

Water flux and daily energy expenditure were measured with doubly labeled water (3HH18O) in two insectivorous sympatric species of Lacertidae of Kerkennah islands (Tunisia), Eremias olivieri (mean body mass: 1.1 g) and Acanthodactylus pardalis (4.5 g) in a semiarid environment. Water turnover and field metabolic rate of Eremias olivieri (174 μL H2O g−1 d−1 and 250 J g−1 d−1) were, respectively, 2.5 and 5 times higher than those of Acanthodactylus pardalis (70 μL H2O g−1 d−1 and 52 J g−1 d−1). The water turnover of Eremias olivieri is one of the highest known among insectivorous lizards, and the daily energy expenditure of Acanthodactylus pardalis one of the lowest. The most plausible explanations are the differences in the size of the prey eaten by each species at this time of the season and in the duration of daily activity; the daily activity of Acanthodactylus pardalis is short (4.5 h d−1) although it is a sit-and-wait predator, whereas Eremias olivieri is active regularly every day for a longer period (7.5 h d−1) although it is an active forager. The high values of water turnover in Eremias olivieri suggest that food is not the only source of water for lizards in this particular insular environment.

scholarly journals Energy expenditure of free-living reindeer estimated by the doubly labelled water method

Rangifer ◽  
2000 ◽  
Vol 20 (2-3) ◽  
pp. 211 ◽  
Author(s):  
Geir Gotaas ◽  
Eric Milne ◽  
Paul Haggarty ◽  
Nicholas J.C. Tyler
Keyword(s):  
Energy Expenditure ◽  
Rangifer Tarandus ◽  
Water Flux ◽  
Co2 Production ◽  
Wild Ungulates ◽  
Free Living ◽  
Doubly Labelled Water ◽  
Svalbard Reindeer ◽  
Mountain Pasture ◽  
The Mean

The doubly labelled water (DLW) method was used to measure total energy expenditure (TEE) in three male reindeer (Rangifer tarandus tarandus) aged 22 months in winter (February) while the animals were living unrestricted at natural mountain pasture in northern Norway (69°20'N). The concentrations of 2H and l8O were measured in water extracted from samples of faeces collecred from the animals 0.4 and 11.2 days after injection of the isotopes. Calculated rates of water flux and CO2-production were adjusted to compensate for estimated losses of 2H in faecal solids and in methane produced by microbial fermentation of forage in the rumen. The mean specific TEE in the three animals was 3.057 W.kg-1 (range 2.436 - 3.728 W.kg1). This value is 64% higher than TEE measured by the DLW method in four captive, non-pregnant adult female reindeer in winter and probably mainly reflects higher levels of locomotor activity in the free-living animals. Previous estimates of TEE in free-living Rangifer in winter based on factorial models range from 3.038 W.kg-1 in female woodland caribou (R. t. caribou) to 1.813 W.kg-1 in female Svalbard reindeer (R. t. platyrhynchus). Thus, it seems that existing factorial models are unlikely to overestimate TEE in reindeer/caribou: they may, instead, be unduly conservative. While the present study serves as a general validation of the factorial approach, we suggest that the route to progress in the understanding of field energetics in wild ungulates is via application of the DLW method.

Determining energy expenditure in preterm infants: comparison of 2H(2)18O method and indirect calorimetry

1992 ◽  
Vol 263 (3) ◽  
pp. R685-R692 ◽  
Author(s):  
C. L. Jensen ◽  
N. F. Butte ◽  
W. W. Wong ◽  
J. K. Moon
Keyword(s):  
Heart Rate ◽  
Energy Expenditure ◽  
Preterm Infants ◽  
Indirect Calorimetry ◽  
Water Flux ◽  
High Ratio ◽  
Individual Variability ◽  
Study Time ◽  
Co2 Production ◽  
Turnover Rates

The doubly labeled water (2H(2)18O) method used to estimate total energy expenditure (EETotal) is particularly sensitive to analytic error in preterm infants, because of their high percentage of body water and the high ratio of water flux to CO2 production. To evaluate further use of this method, the EE of 12 preterm infants was measured by indirect calorimetry and 2H(2)18O simultaneously and continuously for 5 days. Initial infant weight, age, and postconceptional age were (means +/- SD) 1,674 +/- 173 g, 4.4 +/- 2.6 wk, and 34.6 +/- 1.6 wk, respectively. The indirect calorimeter system included an air-temperature-controlled chamber and heart rate monitor. EE was measured by indirect calorimetry for 85.6 +/- 4.7% of study time and estimated from the linear regression of heart rate on EE for 14.4 +/- 4.7% of study time. The 2H(2)18O method entailed an initial dose of 100 mg 2H2O and 250 mg 18O/kg and a final dose of 75 mg 18O/kg; urine was collected twice daily. 2H and 18O enrichments were measured by gas-isotope-ratio mass spectrometry. EE was calculated from measured 2H and 18O dilution spaces (NH, NO), turnover rates (kH, kO), and measured respiratory quotient. The ratio of 2H to 18O dilution spaces was 1.01 +/- 0.01 and the ratio of kO to kH was 1.16 +/- 0.04. Estimation of EE from 2H(2)18O and indirect calorimetry agreed within 1%, although individual variability in methods was large.

Field Metabolism and Food Consumption of Savannah Sparrows during the Breeding Season

The Auk ◽  
1987 ◽  
Vol 104 (2) ◽  
pp. 277-289 ◽  
Author(s):  
Joseph B. Williams
Keyword(s):  
Energy Expenditure ◽  
Brood Size ◽  
Water Flux ◽  
Water Losses ◽  
Time Activity ◽  
Passerculus Sandwichensis ◽  
Nestling Period ◽  
Relationship Construction ◽  
The Relationship ◽  
Savannah Sparrows

Abstract I applied the doubly labeled water (DLW) technique to measure rates of water flux and energy expenditure of Savannah Sparrows (Passerculus sandwichensis) during two breeding seasons on Kent Island, New Brunswick, Canada. Simultaneous to DLW measurements, I constructed time-activity budgets for territorial males, monitored nest attentiveness for incubating females, and quantified frequency of nest visitation for parents feeding young. To ascertain the relationship between brood size and adult energy expenditure, I measured the energy expenditure of adults feeding 2, 4, and 6 nestlings. There was little difference in field metabolic rates (FMR) between territorial males [161.0\pm 21.7 (SD) ml CO2/h). and males that fed 4 nestlings (157.6 ± 19.7 ml CO2/h). Incubating females expired CO2 at rates lower than males during the same time period (134.4 ± 7.9 vs. $161.0 ± 21.7 ml CO2/h but similar to rates for females feeding 4 young, the normal brood size ($134.4 ± 7.9 ml CO2/h for incubating females vs. $136.5 ± 26.9 ml CO2h for females feeding young). Incubating females expended energy at a lower rate than females making 8 or more trips to the nest per hour, the average feeding rate for females late in the nestling period. For males and females together, water influx and efflux rates averaged 17.1 ± 3.2 and 17.2 ± 3.0 ml H20/day, suggesting that birds balanced water intake against water losses. Mean daily solar radiation (MDSR; W/ m2) also influenced FMR during the nestling period. The equation ml CO2/h=172.6-0.07 (MDSR) described the relationship. When brood sizes were manipulated, parents responded by altering their frequency of nest visitation; as frequency increased, so did the FMR of females but not of males. The equation ml CO2/h =98.4 + 5.3 (mean visits/h) described the relationship. Construction of a food budget indicated that, on average, territorial males consumed 21.1 g fresh arthropods per day, while incubating females ingested 17.5 g/day or 210.0 g during the 12-day incubation period. Through the 8-day nestling period, males augmented their foraging by 75%, females by 87%, to feed a brood of 4.

scholarly journals Field Metabolism and Water Flux of Carolina Chickadees During Breeding and Nonbreeding Seasons: A Test of the “Peak-Demand” and “Reallocation” Hypotheses

The Condor ◽  
2001 ◽  
Vol 103 (2) ◽  
pp. 370-375 ◽  
Author(s):  
Paul F. Doherty ◽  
Joseph B. Williams ◽  
Thomas C. Grubb
Keyword(s):  
Body Size ◽  
Energy Expenditure ◽  
Breeding Season ◽  
Water Flux ◽  
Doubly Labeled Water ◽  
Peak Demand ◽  
Nonbreeding Season ◽  
Poecile Carolinensis ◽  
Northern Edge ◽  
Carolina Chickadees

AbstractWe tested the “peak-demand” and “reallocation” hypotheses of seasonal energy expenditure which predict, respectively, that energy expenditure is greatest during the breeding season or varies little seasonally. We tested these predictions by utilizing the doubly labeled water technique to estimate energy expenditure and water flux of Carolina Chickadees (Poecile carolinensis) in both the breeding and nonbreeding seasons. Similar to Weathers et al. (1999), we did not find support for either of these hypotheses, finding instead that energy expenditure was greater during the nonbreeding season. The fact that our study site was at the northern edge of the species' range, where winters are severe, may have influenced this result. Comparisons with other parid studies were equivocal because body size was an important factor in explaining seasonal energetics, and only the larger species have been examined during the breeding season.

Daily Energy Expenditure and Water Flux of Free-Living Blanford's Foxes (Vulpes cana), a small Desert Carnivore

10.2307/5616 ◽  
1992 ◽  
Vol 61 (3) ◽  
pp. 611 ◽  
Author(s):  
Eli Geffen ◽  
A. Allan Degen ◽  
Michael Kam ◽  
Reuven Hefner ◽  
Kenneth A. Nagy
Keyword(s):  
Energy Expenditure ◽  
Water Flux ◽  
Daily Energy Expenditure ◽  
Free Living ◽  
Daily Energy

scholarly journals Estimation of energy expenditure in free-living red deer (Cervus elaphus) with the doubly-labelled water method

1998 ◽  
Vol 80 (3) ◽  
pp. 263-272 ◽  
Author(s):  
P. Haggarty ◽  
J. J. Robinson ◽  
J. Ashton ◽  
E. Milne ◽  
C. L. Adam ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Cervus Elaphus ◽  
Red Deer ◽  
Water Flux ◽  
Climatic Conditions ◽  
Free Living ◽  
Doubly Labelled Water ◽  
The Mean ◽  
Distribution Spaces ◽  
Living Adult

Energy expenditure was estimated using the doubly-labelled water (DLW) method in summer in five free-living adult, non-pregnant, non-lactating, red deer (Cervus elaphus) hinds (weight 107.3 (se 0.9) kg; age 6 (se 1) years) on lowland pasture under typical farming conditions. Climatic conditions were monitored throughout the experiment. Errors due to 2H losses in CH4 and faeces were calculated from previous estimates of stoichiometries. CH4 production, fractionated water loss, urinary N and O2 consumption were estimated using an iterative approach. The water flux (rH2O) in these animals consuming only fresh grass was 12 (se 0.5) kg/d, the CO2 production (rCO2) was 1271 (se 4.0) litres/d and the mean energy expenditure was 25 (se 0.8) MJ/d. There were no significant differences in the isotope distribution spaces and flux rates, rH2O, rCO2 or energy expenditure using the multi-point or two-point approaches to calculation. The DLW-derived energy expenditure of 25 MJ/d is approximately 20% higher than the recommended intake of 21 MJ/d for adult hinds kept outdoors (Adam, 1986) and, at 757 kJ/kg0.75 per d, one third higher than the value of 570 kJ/kg0.75 per d for stags penned indoors (Key et al. 1984).

scholarly journals High Rates of Energy Expenditure and Water Flux in Free‐Ranging Point Reyes Mountain BeaversAplodontia rufa phaea

2007 ◽  
Vol 80 (6) ◽  
pp. 635-642
Author(s):  
Daniel E. Crocker ◽  
Nathan Kofahl ◽  
Gary D. Fellers ◽  
Natalie B. Gates ◽  
Dorian S. Houser
Keyword(s):  
Energy Expenditure ◽  
Water Flux ◽  
Point Reyes ◽  
Free Ranging
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