scholarly journals The energy cost of fat and protein deposition in the rat

1977 ◽  
Vol 37 (3) ◽  
pp. 355-363 ◽  
Author(s):  
J. D. Pullar ◽  
A. J. F. Webster

1. Measurements were made of energy balance by direct calorimetry, and of nitrogen balance in groups of lean and congenitally obese (‘fatty’) Zucker rats at body-weights of 200 and 350 g given a highly digestible semisynthetic diet at 14.0 or 18.4 g/rat per 24 h.2. Losses of food energy and N in faeces were very small. The fatty rats lost much more N in urine than did lean rats. Despite this the proportion of gross energy that was metabolized was 0.92 for both fatty and lean rats.3. In all trials, fatty rats lost a smaller proportion of metabolizable energy (ME) as heat and deposited less as protein than thin rats but deposited much more as fat.4. The amounts of ME required to deposit 1 kJ of protein and 1 kJ of fat respectively were shown by regression analysis to be 2.25 (±0.16) and 1.36 (±0.06) kJ respectively. These values agree extremely closely with recent, more tentative, estimates based on assumptions as to maintenance requirement which the present experiments were able to circumvent. It may be concluded with confidence that the energy costs of depositing 1 g of protein or fat are almost identical at 53 kJ ME/g.

1973 ◽  
Vol 81 (2) ◽  
pp. 295-302 ◽  
Author(s):  
G. Burlacu ◽  
G. Băia ◽  
Dumitra Ionilă ◽  
Doina Moisa ◽  
V. Taṣcenco ◽  
...  

SummaryThe efficiency of utilization of the energy of food by weaned pigs of the Large White breed was measured. Three diets based on maize (40–60%) had a metabolizable energy of 75·8±1·2% of the gross energy, and 78·2 ±3·4% of the metabolizable energy was present as net energy.The maintenance requirement of metabolizable energy of pigs weighing 14·3 ± 2·1 kg was 143·6 kcal/kg°0·75/24 h (601 kJ/kg0·75/24 h).The energy cost per g protein and fat synthesized by piglets was estimated to be 7·43 and 12·05 kcal (31·1 and 50·4 kJ) metabolizable energy, respectively.Equations for calculation of metabolizable energy (Yl, kcal) and of the net energy (Y2, kcal), based on digested nutrients, were:Y1 = 4·64×1 + 9·12×2 + 4·25×3'CV = ± 1·2%,Y2 = 3·84×1 + 7·09×2 + 3·28×3'CV = ± 1·4%,where X1 = g protein digested, X2 = g fat digested, X3= g carbohydrate digested (crude fibre × N-free extracts).


2019 ◽  
Vol 99 (2) ◽  
pp. 315-325
Author(s):  
F. Xie ◽  
Y.K. Li ◽  
J.B. Zhao ◽  
Z.C. Li ◽  
L. Liu ◽  
...  

This study was conducted to determine the digestible energy (DE) and metabolizable energy (ME) values and apparent total tract digestibility (ATTD) of nutrients in four fibrous ingredients [corn distillers’ dried grains with solubles (DDGS), soybean hull, wheat bran, and corn bran] fed to barrows at three different growth stages. Thirty growing barrows, 30 finishing barrows, and 30 fattening barrows (initial body weights of 29.04, 58.57, and 105.65 kg, respectively) were individually housed in metabolism crates and allotted to one of four test diets or a basal corn–soybean meal diet in a 3 × 5 factorial design. Fecal and urine samples were collected for 5 d after a 12 d adaption period. The DE and ME values and ATTD of gross energy (GE), organic matter (OM), crude protein, and acid detergent fiber (ADF) in wheat bran, as well as the ATTD of GE, OM, neutral detergent fiber (NDF), and ADF in corn DDGS, and ATTD of NDF and ADF in soybean hull, were greater (P < 0.05) in pigs at stage 3 compared with those at stages 1 and 2. In conclusion, both body weight and fibrous ingredients have effects on energy values and nutrient digestibility in barrows.


1976 ◽  
Vol 56 (4) ◽  
pp. 775-782 ◽  
Author(s):  
I. R. SIBBALD ◽  
K. PRICE

Canadian barleys, having bulk densities ranging from 40.0 to 70.2 kg/hl, were assayed for true metabolizable energy (TME), gross energy, ether extract, crude fibre, protein, ash, calcium, phosphorus, starch and sugar. Regression analysis showed that from 76 to 84% of the variation in TME values was accounted for by published techniques for predicting metabolizable energy values from chemical composition data. The TME value of barley was correlated with bulk density (r = 0.912 at 29 df) and crude fibre (−0.904 at 30 df). There were also highly significant (P < 0.01) correlations between TME and starch (0.833), starch + sugar (0.838) and ash (−0.758). Earlier studies have not found close relationships between metabolizable energy and the aforementioned physical and chemical parameters. The probable explanation is that TME values are not affected by variations in feed intake associated with differences in palatability whereas the earlier energy measures were subject to this form of variation.


1971 ◽  
Vol 77 (3) ◽  
pp. 405-411 ◽  
Author(s):  
Gh. Burlacu ◽  
Margareta Baltac

SUMMARYThe efficiency of utilization of the energy of food in White Leghorn laying hens for egg production was measured. A ration with a gross energy of 4469 kcal/kg dry matter and 19·4% crude protein had a metabolizable energy of 80·1±1·7% of the gross energy, and 78·5±5·3% of the metabolizable energy was present as net energy.The maintenance requirement of metabolizable energy of White Leghorn hens weighing 1·723±48·5 kg and a production of 19·3±0–49 eggs per month was 125·8 kcal/kg0·75/24 hr.The energy cost per g of protein and fat synthesized by laying White Leghorn hens was estimated to be 7·20 and 12·13 kcal metabolizable energy respectively.


1982 ◽  
Vol 242 (1) ◽  
pp. E19-E24
Author(s):  
C. P. Chan ◽  
L. J. Koong ◽  
J. S. Stern

Five-week-old male obese and lean Zucker rats were made comparably diabetic by intracardiac injections of alloxan (65-72 mg/kg body wt). Lean rats were then given daily injections of protamine zinc insulin at 3 doses: 0.25, 1.25, and 4.0 U.100 g body wt-1.day-1 for 3 wk. Obese rats received identical amounts as corresponding lean controls independent of body weights. The drop of blood glucose concentration after injections of regular insulin and the percentage fall in radioactive plasma insulin after injections of 125I-insulin were comparable in lean and obese rats. Weight gain, fat gain, and protein gain over 21 days increased with increasing amounts of insulin administered. However, at the same dose of insulin, although weight gain was comparable, fat gain was higher and protein gain was lower in obese rats when compared to lean controls. These results suggest that the enhanced lipid deposition of the obese Zucker rat is not totally dependent on insulin levels, but is exaggerated by hyperinsulinemia.


2010 ◽  
Vol 39 (10) ◽  
pp. 2237-2245 ◽  
Author(s):  
Edney Pereira da Silva ◽  
Carlos Bôa-Viagem Rabello ◽  
Luiz Fernando Teixeira Albino ◽  
Jorge Victor Ludke ◽  
Michele Bernardino de Lima ◽  
...  

This research aimed at generating and evaluating prediction equations to estimate metabolizable energy values in poultry offal meal. The used information refers to values of apparent and true metabolizable energy corrected for nitrogen balance (AMEn and TMEn) and for chemical composition of poultry offal meal. The literature review only included published papers on poultry offal meal developed in Brazil, and that had AMEn and TMEn values obtained by the total excreta collection method from growing broiler chickens and the chemical composition in crude protein (CP), ether extract (EE), mineral matter (MM), gross energy (GE), calcium (Ca) and phosphorus (P). The general equation obtained to estimate AMEn values of poultry offal meal was: AMEn = -2315.69 + 31.4439(CP) + 29.7697(MM) + 0.7689(GE) - 49.3611(Ca), R² = 72%. For meals with high fat contents (higher than 15%) and low mineral matter contents (lower than 10%), it is suggest the use of the equation AMEn = + 3245.07 + 46.8428(EE), R² = 76%, and for meals with high mineral matter content (higher than 10%), it is suggest the equations AMEn = 4059.15 - 440.397(P), R² = 82%. To estimate values of TMEn, it is suggested for meals with high mineral matter content the equation: TMEn = 5092.57 - 115.647(MM), R² = 78%, and for those with low contents of this component, the option is the equation: TMEn = 3617.83 - 15.7988(CP) - 18.2323(EE) - 96.3884(MM) + 0.4874(GE), R² = 76%.


1974 ◽  
Vol 19 (3) ◽  
pp. 359-365 ◽  
Author(s):  
M. Ivan ◽  
L. R. Giles ◽  
A. R. Alimon ◽  
D. J. Farrell

SUMMARY1. A split-plot design was used to study apparent digestibility of dry matter, gross energy and nitrogen of a whole grain wheat diet and processed (hammermilled, rolled or hammermilled and then steam-pelleted) wheat diets by eight small (33·9 ± 0·1 kg) and eight large (70±1·7 kg) pigs. Metabolizable energy and nitrogen retention were also studied with the small pigs.2. The processed wheat diets were superior to the whole grain wheat diet in all the parameters measured.3. There were no significant differences between the performance of pigs given the differently processed wheat diets.4. Apparent digestibility of dietary components particularly in the whole wheat diet was significantly higher when diets were given to small pigs than when given to large pigs.


1978 ◽  
Vol 90 (1) ◽  
pp. 47-68 ◽  
Author(s):  
K. L. Blaxter ◽  
A. W. Boyne

SUMMARYThe results of 80 calorimetric experiments with sheep and cattle, mostly conducted in Scotland, were analysed using a generalization of the Mitscherlich equation R = B(l–exp(–pG))–l, where R is daily energy retention and G daily gross energy intake, both scaled by dividing by the fasting metabolism. The relations between gross energy and metabolizable energy were also examined. Methods of fitting the Mitscherlich equation and the errors associated with it are presented.It is shown that the gross energy of the organic matter of feed can be estimated from proximate principles with an error of ±2·3% (coefficient of variation) and that provided different classes of feed are distinguished, the metabolizable energy of organic matter can be estimated from gross energy and crude fibre content with an error of ±6·9%. Parameters of the primary equation made with cattle agreed with those made with sheep and there was no evidence of non-proportionality of responses on substitution of feeds in mixtures.The efficiency of utilization of gross energy for maintenance and for body gain of energy was related to the metabolizability of gross energy and, in addition, to fibre or to protein content. Prediction equations are presented which describe these relationships.It is shown that the primary equation can be manipulated to express a number of biological concepts and that its two parameters B and p can be simply derived from estimates of the two efficiency terms for maintenance and production.The results are discussed in relation to the design of feeding systems for ruminant animals and to the derivation of optima in their feeding.


1972 ◽  
Vol 79 (1) ◽  
pp. 99-103 ◽  
Author(s):  
A. M. Raven

SUMMARYA 6 x 6 Latin Square balance experiment was carried out using six Friesian steers, each of which initially weighed about 304 kg. The six treatments studied were an all-hay diet and five other diets containing 20,40,60,80 and 100 % of rolled barley fortified with mineral and vitamin supplements, accompanied by correspondingly reduced proportions of hay. Each diet was fed at an estimated maintenance level of feeding.The progressive increase in the proportion of concentrate gave a significantly linear increase (P < 0·001) in both digestible and calculated metabolizable energy. The actual increase in digestible energy was from 2·62Mcal/kg dry matter (59·3% of the gross energy) on the all-hay treatment to 3·42 Mcal/kg dry matter (79·5% of the gross energy) on the all-concentrate treatment. Use of the determined digestible energy values for the all-hay and fortified barley diets to calculate the digestible energy of the four mixed diets gave results in reasonably good agreement with the determined values, the maximum difference being 0·12 Mcal/kg dry matter, which represented 3·83 % of the determined value. The losses of energy in the urine expressed as percentages of the gross energy of the diets showed a small but significantly linear decrease (P < 0·01) with increase in proportion of barley in the diet. The molar proportions of steamvolatile acids in samples of rumen fluid taken from two animals on each treatment indicated that increase in the proportion of concentrate was associated with tendencies for increase in acetic acid, decrease in propionic acid and little change in butyric acid. The mean digestibility of the organic matter was 62·6 % on the all-hay treatment and 81·8 % on the all concentrate treatment. The progressive increase in the proportion of concentrate gave a significantly linear increase (P < 0·001) in digestibility of the organic matter. Although intakes of nitrogen decreased with increase in the proportion of concentrate due to a decrease in the amount of dry matter fed, the weights of nitrogen retained were well maintained and when expressed as percentages of intake showed a significantly linear increase (P < 0·01).


1983 ◽  
Vol 100 (3) ◽  
pp. 717-722
Author(s):  
J. B. Moran

SUMMARYIndonesian Ongole and swamp buffalo bulls that had previously been given 0, 1·2, 2·4, 3·6 or 4·8 kg/head/day rice bran plus ad libitum elephant grass were slaughtered after 161 days feeding. Abdominal depot fat, full and empty reticulo-rumen and cold carcass weights were recorded. Various carcass variables were measured and the 9–10–11 rib joints were dissected into bone, muscle and fat. Carcass gross energy was calculated from rib-fat content using previously determined regression equations. Feed efficiency was expressed in terms of the ratios of live-weight gain or carcass-energy accretion to metabolizable energy available for growth.Increasing supplementation with rice bran resulted in larger abdominal fat depots, higher dressing percentages, increased carcass fatness (and hence carcass gross energy) and improved rib muscle to bone ratios. Carcass conformation was unaffected by dietary treatment. When feed efficiency was expressed per unit live-weight gain, there was a decrease with increasing rice-bran feeding. Feed efficiency, expressed per unit of carcass energy accretion, improved with rice-bran supplementation and was generally higher in buffalo than in Ongole bulls. Dietary and species differences in feed efficiency could be primarily explained by the differential energy cost of deposition of, and the availability of energy from, carcass protein and lipid.


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