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PubMed1990

[The energy requirements of Holstein-Friesian heifers during rearing and pregnancy under the tropical conditions of Cuba. 1. Determination of dry matter and energy assimilation and of the live weight development and energy expenditure].

In an individual feeding experiment with 48 Holstein-Friesian heifers divided into 3 groups, the effect of various energy levels on live weight development and energy expenditure in the age bracket of 97 days (78 kg live weight) to conception (350 kg LW) and from conception to calving (500 kg LW) was investigated. Rations with differing concentrate--roughage ratios were used. The differentiation of energy intake per day between groups 1 and 2 and group 3 amounted to 7.5% in the 1st development period and to 20% between group 1 and groups 2 and 3 in the 2nd development period. There were significant differences in the live weight gain of 95 g/animal and day in the first development period (up to conception) and of 81 g/animal and day in the second period of development (from conception to calving). Under the tropical climatic conditions the energy expenditure in these studies was approximately 10% under the energy expenditure recommended by the NRC (1978). While there was a clear reciprocal relation between energy expenditure and live weight gain in the first period of development, this relation was less distinct in the second period of development.

Age Factors↗
PubMed1993

Metabolic utilization of dietary energy and nutrients for maintenance energy requirements in sows: basis for a net energy system.

Digestible energy (DE), metabolizable energy (ME) and net energy for maintenance (NEm) values of a set of fourteen diets were measured in six adult sows fed at and below their maintenance energy level. The efficiency of ME for NEm was estimated from heat production (HP) measurements (indirect calorimetry) at these different feeding levels. HP was partitioned between HP due to physical activity, thermic effect of food (TEF) and fasting heat production (FHP). The amounts of DE digested in the small intestine or in the hindgut were measured. Equations for prediction of NEm from dietary characteristics were calculated. HP at maintenance level averaged 400 kJ/kg body-weight0.75, 16 and 19% of the total being due to physical activity and TEF respectively. The efficiency of ME for NEm averaged 77.4% with higher values for digestible diethyl ether extract (100%) and starch+sugar (82%). The efficiencies of digestible crude protein (N x 6.25) and digestible residue averaged 69 and 56% respectively. The energy absorbed from the small intestine was used more efficiently than the energy fermented in the hindgut (82 v. 59%). These values are comparable with those obtained in growing pigs. The NEm content of diets can be predicted accurately from equations including DE (or ME) values and some dietary chemical characteristics.

Animal Feed↗
PubMed2000

Resting energy expenditure, activity energy expenditure and total energy expenditure at age 91-96 years.

There is a limited knowledge concerning energy requirements of the elderly, especially the oldest old (> 80 years). Energy requirements should be estimated from measurements of energy expenditure. For this purpose twenty-one free-living individuals (eight males, thirteen females) aged 91-96 years living in Göteborg, Sweden were studied. Total body water (TBW) measured by the doubly-labelled-water (DLW) technique was 29.5 (sd 5.4) kg in females and 35.6 (sd 4.3) kg in males. TBW measured using bioelectric impedance (BIA) was 31.6 (sd 6.4) kg in females and 42.0 (sd 7.4) kg in males. The mean difference between TBW measured by BIA and that measured by DLW was 3.54 (sd 3.6) kg (P = 0.0002). Resting metabolic rate (RMR) was measured using a ventilated-hood system and averaged 5.36 (sd 0.71) MJ/d in females (n 12) and 6.09 (sd 0.91) MJ/d in males (n 8). Difference between measured RMR and predicted BMR (n 20) was 0.015 (sd 0.86) MJ/d (NS). Total energy expenditure (TEE) measured by DLW averaged 6.3 (sd 0.81) MJ/d in females and 8.1 (sd 0.73) MJ/d in males. Activity energy expenditure (TEE - RMR), thus including diet-induced thermogenesis (DIT), averaged 0.95 (sd 0.95) MJ/d in females (n 12) and 2.02 (sd 1.13) MJ/d in males. Physical activity level (TEE/BMR) averaged 1.19 (sd 0. 19) in females and 1.36 (sd 0.21) (P = 0.08) in males. If DIT is assumed to be 10 % of the TEE, energy spent on physical activity will be very low in this population.

Aged↗
PubMed1991

The energy expenditure and nutritional status of college students. I. The energy cost and the total energy expenditure per day.

The energy cost of major activities was determined in healthy students. Among the 606 medical students, 319 were males and 287 were females. Their ages ranged from 18 to 24 years. Douglas' method was used to measure energy cost of each of a total of 42 activities, as well as that of the basal metabolic rates (BMR), resting metabolic rates (RMR) and the total energy expenditure per day under normal situations. The average RMR of male and female subjects were 0.669 +/- 0.033 and 0.656 +/- 0.030 kcal/sq.m/min respectively. The total energy expenditure per day of male students were 2706 kcal, and 2373 kcal for female students. The energy cost of single activities can be used as the basal data in studies of energy metabolism.

Adolescent↗
PubMed1987

Relations between enzyme activities connected with energy metabolism and parameters of food energy utilization in young and adult rats. Part 1. Studies on dietary effects on weight, body composition and energy gain.

Weaned male Wistar rats were fed ad libitum besides standard pellets a normal-protein (NP), a low-protein (LP) and a high-fat (HF) diet for different periods of time. In comparison to rats on the NP diet the body weight of the LP group was significantly lower after seven weeks feeding, not after a duration of about forty weeks. No remarkable diet-related differences were detected by determination of the mean body composition and of the relative gross energy content of the body neither after seven nor forty weeks. Total gross energy intake was practically identical both for the NP and LP rats irrespective on the duration of the feeding period. A significantly lower quotient of body energy gain/total gross energy intake under the protein-restrictive LP diet after seven weeks suggests the expression of an energy dissipation obviously no longer visible after a long time feeding period.

Animals↗
PubMed2000

Repeated measurements of energy intake, energy expenditure and energy balance in lactating Bangladeshi mothers.

OBJECTIVE: To examine changes in energetic parameters and nutritional status of chronically malnourished lactating women over a period of 13 months postpartum. DESIGN: A study of 15 lactating Bangladeshi mothers, of whom eight were tea pluckers and seven housewives, was conducted over a 13 months period from the birth of the child. Anthropometric measurements and body composition were determined on five occasions (at 3.5, 5.5, 7.5, 10 and 13 months) and energy expenditure (heart rate monitoring method), and energy intake (3-day weighing) on three occasions at 3.5, 10 and 13 months. RESULTS: The mothers, all of whom were of low BMI (range 14.9-18.1 kg/m2 at the end of the study) undertook high levels of physical activity (pluckers more so than housewives). There was evidence of weight loss over the 13 months, particularly between the fourth and sixth months postpartum, mainly due to a significant decrease in fat-free mass. Food intake and expenditure were higher in pluckers than housewives but energy balance was not significantly different, although workers were, on average, in negative balance on all three occasions. Food intake was based on cereals and fat deficient. CONCLUSIONS: A Bangladeshi sample of breast-feeding mothers studied over 13 months postpartum showed evidence of chronic malnutrition with women living on very low fat diets. All mothers, either housewives or tea pluckers were involved in energy demanding activities. There was a general tendency towards negative energy balance. Mothers lost weight, mainly fat-free mass over the study period.

Adaptation, Biological↗
PubMed1982

Maintenance energy: a general model for energy-limited and energy-sufficient growth.

The new model proposed to account for the energy requirement for growth includes both a constant maintenance energy term (m) independent of the specific growth rate and a term (m') which decreases linearly with increase in specific growth rate and becomes zero at the maximum specific growth rate. The available data for testing the model do not deviate significantly from the relations predicted. Consistent values of the maximum growth yield (YG) can be derived, irrespective of whether the cultures are energy limited or energy sufficient. Attention is drawn to the possibility that the constant maintenance energy term may be estimated from the maximum specific growth rate.

Bacteria↗
PubMed1980

Energy and protein nutrition of early-weaned pigs. 1. Effect of energy intake and energy: protein on growth, efficiency and nitrogen utilization of pigs between 8-32 d.

1. The effect of energy and protein intake on the growth, food efficiency and nitrogen retention of artificially-reared pigs was studied over three 8 d periods between 8-32 d of age in an experiment employing a 5 x 3 x 2 factorial design. The factors were initial energy: N value (I; 250, 355, 460, 565 or 670 kJ/g N), rate of increase of I at 8 d intervals (0, 12.5 or 25%) and plane of nutrition (three times daily to appetite or 75% of this intake). 2. The range of energy: N values was obtained by formulating five diets based on dried skim milk, lactose and casein and feeding appropriate combinations of two diets. The diets, which were pelleted, contained 100 g maize oil/kg and the gross energy content was approximately 20 MJ/kg. 3. N digestibility was high at all three age intervals, reaching 0.99 on the diet containing the highest dietary crude protein (N x 6.25) level. Metabolic faecal N excretion was found to be I.I g/kg dry matter (DM) intake. 4. Growth rate, feed conversion ratio (kg food intake/kg wt gain; FCR), N retention (NR) and the proportion of digested N retained (NR: apparent digested N (ADN)) were significantly (P less than 0.001) affected by I values at all age intervals and the responses were quadratic. Response curves were calculated by the least squares method and optimum values of I determined for each of the criteria. A constant energy: N value of approximately 400 kJ/g N was indicated by growth, FCR and NR optima but the NR:ADN value fell from 0.77 for the 8-16 d period to 0.60 for the 24-32 d period at this I value. It is concluded that a suitable compromise would be an I value of 470 kJ/g N increasing by 10%/week. 5. There was a significant interaction between plane of nutrition and I values on FCR between 16-24 d (P less than 0.001) and 8-32 d (P less than 0.01) indicating that FCR was better at high protein levels and worse at low protein levels when the diets were fed on the lower plane of nutrition.

Aging↗
PubMed1990

[Measuring energy turnover in the adult swine during feeding of rations with potato starch, potatoes, beets, pressed shreds and coarse fodder as supplements to a basic ration. 1. Energy turnover and energy utilization].

25 rations with a wide variation of the content of various carbohydrates (crude fibre 36-185; water-soluble carbohydrates 25-306, starch 272-683 g/kg DM) were fed to male castrates (n = 8) of a live weight between 90 and 180 kg, and energy metabolism was measured. The rations were composed of a cereal basic ration and various feed-stuffs (potato starch-raw and soaked) potatoes (raw and steamed), sugar beet and products from it, maize pellets, dried roughage lucerne, clover, lupin, grass, rye straw meal) as supplements. The digestibility and metabolisability of the energy of the rations ranged between 88 and 62 or 86 and 60% resp. Between 2 and 4% of the consumed energy were lost in urine. The partial utilization of the metabolizable energy of the rations varied between 80% (processed supplement of potato starch) and 52% (supplement of rye straw). The rations with supplements of dried roughage were relatively well energetically utilized-between 63 and 70%. A regressively calculated difference of 17%-units was regressively calculated between the utilization of metabolizable energy of either precaecal or postileal origin.

Animal Feed↗
PubMedDate not supplied

[Daily energy consumption, physiological standards of energy requirement and energy value of food rations for children in boarding schools of the Georgian SSR].

To determine daily energy consumption the time budget was studied and energy consumption by children of varying age and sex was calculated at the main postures and types of activity. The data obtained have shown that the energy value of food rations during a year exceeded the physiological energy requirement in schoolchildren of the I age group on the average by 20-35 kcal, while in the II and III age groups it was lower by 30-150 kcal. These results show the necessity of rationalization of nutrition for children in boarding schools of Tbilisi.

Adolescent↗
PubMed1993

[Dependence of gross energy, digestible and metabolizable energy of feed and the energy onset on the content of digestible nutrients in regard to starch and sugar. A contribution to the further development of energetic feed evaluation. 2. Results from studies of cattle].

On the basis of an analysis of energy metabolism measurements on adult cattle (oxen), fed on 110 rations with very heterogeneous nutrient composition, the following prediction equations for gross energy (y1), digestible (y2) and metabolizable energy (y3) as well as for energy deposition effect of rations (y) (kJ) are presented: y1 = 23.6z1 + 34.0z2 + 17.3z3 + 16.0z4 + 19.1z5 y2 = 23.6x1 + 34.0x2 + 17.3x3 + 16.0x4 + 18.0x5 y3 = 17.3x1 + 34.0x2 + 15.9x3 + 15.1x4 + 15.4x5 y = (6.5x + 26.6x2 + 10.1x3 + 7.5x4 + 8.9x5) (-0.5574 + 0.04050x6 - 0.0002633x6(2)) [table: see text]

Animal Feed↗
PubMed2005

Energy transfer between polyatomic molecules. 1. Gateway modes, energy transfer quantities and energy transfer probability density functions in benzene-benzene and Ar-benzene collisions.

We report collisional energy transfer, CET, quantities for polyatomic-polyatomic collisions and use excited benzene collisions with cold benzene bath, B-B, as our sample system and compare our results with the CET of excited benzene with Ar bath. We find that the gateway mode for both systems is the out-of-plane modes and that in B-B CET, vibration to vibration, V-V, is the dominant channel. Rotations play a mechanistic role in the CET but the net rotational energy transfer is small compared to V-V. The shape of the down side of the energy transfer probability density function, P(E,E'), is convex for B-B collisions and it becomes less so as the temperature increases. In Ar-B collisions, P(E,E') is concave and it becomes less so as the temperature decreases. We report average vibrational, rotational, and translational energy transferred, , as function of temperature for various initial conditions.

Journal Article↗
PubMed1975

Energy metabolism of Bdellovibrio bacteriovorus. I. Energy production, ATP pool, energy charge.

Bdellovibrio bacteriovorus, strain Bd. 109 Sa, generates ATP mainly by oxidative phosphorylation during electron transport. During exponential growth the ATP pool is constant (9 mmoles/100 mugN) indicating that energy-producing and energy-consuming reactions are well balanced. The ratio of substrate respiration/endogenous respiration is approx. 2.5/1. Energy charge is constant both in endogenous and substrate respiration at values of 0.62 to 0.64. During endogenous respiration (starvation) the ATP pool oscillates at regular intervals. ATP over-production is started after the ATP pool has decreased to a minimum level of 6 nmoles/100 mug N. The alternating over- and under-production of ATP is interpreted as a special regulation which enables the organism to make economic use of its own cellular materials. Addition of substrate (glutamate) to starving cells does not influence the type of ATP pool oscillation as observed in endogenous respiration. The parasitic strain Bd. 109 Pa exhibits the same periodicity of ATP overproduction as does it saprophytic derivative, Bd. 109 Sa. Decrease of viability during starvation is paralleled by a decrease of the ATP pool.

Adenine Nucleotides↗
PubMed1986

[Nutrient dependence of energy preservation requirements in rats. 1. Dependence of energy requirements for preservation in fully-grown rats on the type of nutrient offered as the sole energy source].

In two experiments with fully-grown albino rats (Wistar strain) the energetic utilization of glucose, sunflower oil and casein in the maintenance metabolism was determined under thermoneutral conditions of keeping the animals. The relative requirement of metabolizable energy for maintenance was, with either glucose, sunflower oil or casein being the sole energy source of the feed, in experiment 1 100:105:133 and in experiment 2 100:102:135. The absolute values of the maintenance requirement of metabolizable energy were in experiment 1 347 +/- 26, 364 +/- 61 and 460 +/- 33 resp., and in experiment 2 330 +/- 11, 337 +/- 21 and 446 +/- 27 kJ/kg LW 0.75 resp. The results are discussed in connection with the efficiency of ATP synthesis (metabolizable energy/mol ATP gain) in the oxidative decomposition of nutrients.

Adenosine Triphosphate↗
PubMed1995

[Investigations of empty body weight gain, on protein, fat and energy disposition as well as on utilization of metabolizable energy for energy deposition in black and white bulls. 1. Empty body weight gain].

Six series of individual feeding experiments (altogether 544 animals) with different energy supply and connected with steps slaughteries and whole-body analyses, constructed carried out and analysed upon the same aspects, were regression analytically interpreted with the aim of quantify the relation of empty body weight to live weight. The relation of empty body weight to live weight showed a nonlinear dependence on the live weight as well as on the age of animals. The assessment of the metabolizability of energy of the diet as an additional variable reduced the residual variation considerably. Therefore from the knowledge of live weight or age of the animals, and the metabolizability of energy of the diet the relation of empty body weight to live weight of black and white bulls could be calculated. Moreover, the relation of empty body weight gain to live weight gain in dependence on live weight and live weight gain was investigated.

Animal Feed↗
PubMed1983

Energy imparted, energy transferred and net energy transferred.

The ICRU-defined non-stochastic quantity absorbed dose is related to the stochastic quantity energy imparted. In this paper the corresponding stochastic quantities energy transferred and net energy transferred are defined as precursors for kerma and collision kerma, respectively. This forms a rational fundamental framework for radiation dosimetry which facilitates its teaching and understanding.

Energy Transfer↗
PubMed2003

An evaluation of the sensitivity and specificity of energy expenditure measured by heart rate and the Goldberg cut-off for energy intake: basal metabolic rate for identifying mis-reporting of energy intake by adults and children: a retrospective analysis.

OBJECTIVE: To identify adults and children as under- (UR), acceptable (AR), or over-reporters (OR) of energy intake (EI) using energy expenditure measured by doubly labelled water (DLW) (EE(DLW)), and to use this as a reference to determine the sensitivity and specificity of (i) EE measured by heart rate (EE(HR)), and (ii) the Goldberg cut-off technique for classifying subjects into the same categories. DESIGN: Retrospective analysis of a dataset comprising concurrent measurements of EE(DLW), EE(HR), basal metabolic rate (BMR), and EI by weighed record (EI(WR)) on 14 adults and 36 children. EI by diet history (EI(DH)) was also measured in the children only. EI(WR):EE(DLW) provided the reference definition of subjects as UR, AR or OR. Three strategies for classifying mis-reporters based on EE(HR) and Goldberg cut-offs were then explored. Sensitivity and specificity were calculated respectively as the proportion of UR and non-UR correctly identified. RESULTS: Approximately 80% of all subjects were AR. For EI(WR) and EI(DH) respectively, the sensitivity of EE(HR) was 0.50 and 1.00, and specificity was 0.98 and 1.00. Although designating subjects as having low, medium or high activity levels (EE(HR):BMR(meas)) and calculating cut-offs based on appropriate WHO physical activity level PALs did not change sensitivity, specificity dropped to 0.98 (EI(WR)) and 0.97 (EI(DH)). Cut-offs based on a PAL of 1.55 reduced sensitivity to 0.33 (EI(WR)) and 0.00 (EI(DH)), but specificity remained unchanged. The sensitivity of all cut-offs based on physical activity level (PALs) for EI(WR) was 0.50 (adults) and 0.25 (children). CONCLUSIONS: If the precision of EE(HR) was improved, it may be useful for identifying mis-reporters of EI.

Adolescent↗