A note on the effects of body fatness and level of food intake on the rate of fat loss in lactating ewes

1982 ◽  
Vol 34 (3) ◽  
pp. 355-357 ◽  
Author(s):  
R. T. Cowan ◽  
J. J. Robinson ◽  
I. McDonald
Keyword(s):  
Food Intake ◽  
Energy Intake ◽  
Body Fat ◽  
Metabolizable Energy ◽  
Body Fatness ◽  
Fat Loss ◽  
Body Fat Content ◽  
Metabolizable Energy Intake ◽  
Image Position ◽  
The Relationship

ABSTRACTData from three comparative slaughter experiments involving a total of 73 ewes were used to study the influence of body fat content at the start of lactation (X1 kg) and of metabolizable energy intake (X2, MJ/day), on the rate of loss of body fat by lactating ewes over the first 6 weeks of lactation (Y, g/day). The relationship was described by the equation:Thus the rate of fat loss was greater for ewes with higher initial fat contents, but the differential became less as metabolizable energy intake increased. Since increases in body fatness depress food intake it was not possible to prevent loss of body fat during early lactation in fat ewes given high concentrate diets ad libitum. The likely response in milk yield to increase in body fatness at parturition is therefore strongly dependent on the relative levels of body fatness and metabolizable energy intake. The value of any improvement in condition of the ewe at parturition may be considerable when metabolizable energy intake during lactation is low but much less when it is expected to be high.

scholarly journals 223 Evaluation of dietary characteristics and empty body chemical components affecting the relationship between heat production and metabolizable energy intake in growing beef cattle

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 158-159
Author(s):  
Phillip A Lancaster
Keyword(s):  
Chemical Composition ◽  
Energy Intake ◽  
Body Fat ◽  
Heat Production ◽  
Metabolizable Energy ◽  
Energy Concentration ◽  
Chemical Components ◽  
Data Set ◽  
Metabolizable Energy Intake ◽  
The Relationship

Abstract Metabolizable energy required for maintenance varies with diet and empty body chemical composition. The objective was to quantify the relationships of dietary characteristics and empty body chemical composition with heat production. A literature search was performed to compile data (31 studies, 214 treatment means) on metabolizable energy intake (MEI) and composition of empty body gain in growing steers and heifers. Data analysis were performed using R statistical package for mixed models with study as random variable. Nonlinear regression of energy gain (EG) on MEI indicated the relationship was not curvilinear in this data set, likely due to lack of negative values of EG. Further analyses were conducted using a linear model. Dietary characteristics of roughage level (0–100% of diet DM) and CP (10–25% diet DM), metabolizable energy concentration (1.3–3.3 Mcal/kg DM), and roughage type were evaluated in the model. Roughage sources were categorized into no roughage, silage, hay, pellets, silage + pellets, and hay + pellets. Of the empty body chemical components, proportion of fat in the empty body (EBFp) and in the gain (EBFgp) had a significant (P < 0.001) interaction with MEI on HP. Of the dietary characteristics, roughage level and type had a significant (P < 0.001) interaction with MEI on HP; however, when both were included in the model, roughage type was not significant (P > 0.10). The final model was 47.01 ± 12.54 + 0.630 ± 0.05*MEI – 132.3 ± 64.7*EBFp + 0.0007 ± 0.0001*MEI*Roughage level + 0.753 ± 0.24*MEI*EBFp – 0.268 ± 0.032*MEI*EBFgp with an R2 of 0.919 and an AIC of 1614 compared with 0.867 and 1695 for the simple linear regression model of HP on MEI. In conclusion, greater empty body fat decreased the intercept, and greater empty body fat proportion and levels of roughage in the diet increased the slope between HP and MEI, whereas greater percentage of fat in the empty body gain decreased the slope between HP and MEI.

scholarly journals Estimation of the total efficiency of metabolizable energy utilization for maintenance and growth by cattle in tropical conditions

2005 ◽  
Vol 34 (3) ◽  
pp. 1006-1016 ◽  
Author(s):  
Douglas Sampaio Henrique ◽  
Ricardo Augusto Mendonça Vieira ◽  
Pedro Antônio Muniz Malafaia ◽  
Maurício Cordeiro Mancini ◽  
André Luigi Gonçalves
Keyword(s):  
Energy Intake ◽  
Heat Production ◽  
Metabolizable Energy ◽  
Energy Utilization ◽  
Total Efficiency ◽  
Net Energy ◽  
Tropical Conditions ◽  
Metabolizable Energy Intake ◽  
The Relationship ◽  
Direct Measures

Data of 320 animals were obtained from eight comparative slaughter studies performed under tropical conditions and used to estimate the total efficiency of utilization of the metabolizable energy intake (MEI), which varied from 77 to 419 kcal kg-0.75d-1. The provided data also contained direct measures of the recovered energy (RE), which allowed calculating the heat production (HE) by difference. The RE was regressed on MEI and deviations from linearity were evaluated by using the F-test. The respective estimates of the fasting heat production and the intercept and the slope that composes the relationship between RE and MEI were 73 kcal kg-0.75d-1, 42 kcal kg-0.75d-1 and 0.37. Hence, the total efficiency was estimated by dividing the net energy for maintenance and growth by the metabolizable energy intake. The estimated total efficiency of the ME utilization and analogous estimates based on the beef cattle NRC model were employed in an additional study to evaluate their predictive powers in terms of the mean square deviations for both temperate and tropical conditions. The two approaches presented similar predictive powers but the proposed one had a 22% lower mean squared deviation even with its more simplified structure.

A comparative evaluation of functions for the analysis of growth in male broilers

2003 ◽  
Vol 140 (4) ◽  
pp. 451-459 ◽  
Author(s):  
H. DARMANI KUHI ◽  
E. KEBREAB ◽  
S. LOPEZ ◽  
J. FRANCE
Keyword(s):  
Body Weight ◽  
Fixed Point ◽  
Energy Intake ◽  
Body Weight Gain ◽  
Energy Requirement ◽  
Metabolizable Energy ◽  
Wide Range ◽  
Diminishing Returns ◽  
Metabolizable Energy Intake ◽  
The Relationship

Data from six studies with male broilers fed diets covering a wide range of energy and protein were used in the current two analyses. In the first analysis, five models, specifically re-parameterized for analysing energy balance data, were evaluated for their ability to determine metabolizable energy intake at maintenance and efficiency of utilization of metabolizable energy intake for producing gain. In addition to the straight line, two types of functional form were used. They were forms describing (i) diminishing returns behaviour (monomolecular and rectangular hyperbola) and (ii) sigmoidal behaviour with a fixed point of inflection (Gompertz and logistic). These models determined metabolizable energy requirement for maintenance to be in the range 437–573 kJ/kg of body weight/day depending on the model. The values determined for average net energy requirement for body weight gain varied from 7·9 to 11·2 kJ/g of body weight. These values show good agreement with previous studies. In the second analysis, three types of function were assessed as candidates for describing the relationship between body weight and cumulative metabolizable energy intake. The functions used were: (a) monomolecular (diminishing returns behaviour), (b) Gompertz (smooth sigmoidal behaviour with a fixed point of inflection) and (c) Lopez, France and Richards (diminishing returns and sigmoidal behaviour with a variable point of inflection). The results of this analysis demonstrated that equations capable of mimicking the law of diminishing returns describe accurately the relationship between body weight and cumulative metabolizable energy intake in broilers.

The effects of metabolizable energy intake on body fat depots of adult Pelibuey ewes fed roughage diets under tropical conditions

2011 ◽  
Vol 43 (5) ◽  
pp. 929-936 ◽  
Author(s):  
A. J. Chay-Canul ◽  
A. J. Ayala-Burgos ◽  
J. C. Ku-Vera ◽  
J. G. Magaña-Monforte ◽  
L. O. Tedeschi
Keyword(s):  
Energy Intake ◽  
Body Fat ◽  
Metabolizable Energy ◽  
Fat Depots ◽  
Tropical Conditions ◽  
Metabolizable Energy Intake

GLUCOSE METABOLISM IN FAT AND THIN ADULT SHEEP

1984 ◽  
Vol 64 (4) ◽  
pp. 825-832 ◽  
Author(s):  
M. A. McNIVEN
Keyword(s):  
Energy Balance ◽  
Glucose Metabolism ◽  
Energy Intake ◽  
Negative Energy ◽  
Pool Size ◽  
Metabolizable Energy ◽  
Negative Energy Balance ◽  
Body Fatness ◽  
Feeding Level ◽  
Metabolizable Energy Intake

The effect of body fatness on glucose metabolism was studied in six adult crossbred wethers divided into two groups weighing 90 kg (fat) or 55 kg (thin). Glucose turnover measurements were made using 6-3H-glucose by single injection at four levels of metabolizable energy intake: high, 17 MJ/day; intermediate, 10 MJ/day; low, 6 MJ/day; and fasting for both thin and fat groups. The greatest group differences occurred at the high feeding level. Body pool size and glucose space were significantly lower (P < 0.001) for the fat sheep and were reduced at fasting for both fatness levels. The mean irreversible loss rate was not affected by body fatness but was significantly affected (P < 0.001) by feeding level. Glucose recycled as a proportion of total entry rate was significantly affected by body fatness and was dependent on a positive or negative energy balance. When in negative energy balance the sheep maintained blood glucose within the normal range by recycling up to four times more glucose than was utilized. It appears that rate of glucose synthesis is related to energy balance and metabolizable energy intake. A tendency toward insulin insensitivity in the fat sheep could be related to high levels of recycling, and a greater glucose drain or prolonged fast could be more serious with the decreased glucose pool size and space. Key words: Glucose metabolism, ruminant, obese, energy balance

Metabolic response to cold air in men and women in relation to total body fat content

1963 ◽  
Vol 18 (3) ◽  
pp. 603-612 ◽  
Author(s):  
Elsworth R. Buskirk ◽  
Ronald H. Thompson ◽  
G. Donald Whedon
Keyword(s):  
Body Fat ◽  
Metabolic Response ◽  
Previous History ◽  
Minimal Amount ◽  
Body Fatness ◽  
Metabolic Chamber ◽  
Body Fat Content ◽  
History Of ◽  
Total Body ◽  
C 50

Eight healthy young men (ages 19–35), four older men (ages 38–42), three obese subjects (two women and one man, ages 20–34) were individually exposed on one or more occasions to 10 C (50 F) air in the Metabolic Chamber for periods of 2–4 hr. A minimal amount of clothing was worn: the males wore shorts and the females wore halters and shorts. Air movement was routinely less than 50 ft/min and relative humidity 50% or less. Body fatness among the subjects ranged from 13 to 45% of body weight. The metabolic response to cold determined from Vo2 and Vco2 was significantly and inversely related to per cent body fat according to the regression equation: kcal/(m2·hr) = 65.2 – 0.520 (% fat) ± 0.115. Total body insulation after 2 hr of exposure was significantly and directly related to per cent body fat and inversely related to the metabolic response. Despite these significant relationships, wide individual differences were observed in the metabolic response to cold between pairs of subjects of like age, previous history of cold exposure, and body fatness. Submitted on September 27, 1962

Metabolizable energy intake of client-owned adult cats

2015 ◽  
Vol 99 (6) ◽  
pp. 1025-1030 ◽  
Author(s):  
M. Thes ◽  
N. Koeber ◽  
J. Fritz ◽  
F. Wendel ◽  
B. Dobenecker ◽  
...  
Keyword(s):  
Energy Intake ◽  
Metabolizable Energy ◽  
Metabolizable Energy Intake ◽  
Adult Cats
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