Net utilization of roughage and concentrate diets by sheep

1976 ◽  
Vol 35 (2) ◽  
pp. 201-209 ◽  
Author(s):  
P. I. Wilke ◽  
F. J. Van Der Merwe
Keyword(s):  
South African ◽  
Energy Requirement ◽  
Experimental Period ◽  
Energy Gain ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Maintenance Energy ◽  
Energy Retention ◽  
Maintenance Energy Requirement ◽  
Body Energy

1. Two diets, an all-roughage diet and a high-concentrate diet, were fed at two levels, a low level of estimated 1.5 times maintenance energy requirement and a higher level of estimated two times maintenance energy requirement, to South African Mutton Merino castrated male sheep, aged 13 months and in fairly lean condition at the start of the 93 d experimental period..2. Body composition and energy retention were determined using the comparative slaughter technique and two series of digestibility and balance studies were done during the course of the experiment. Metabolizability of each diet was estimated and corrected for fermentation heat using the fermentation balance approach..3. Although there were significantly different rates of energy gain on different diets and feeding levels, fat energy gained (% total energy gained) was similar for the four groups, i.e. 78–80..4. Regression of energy gain v. corrected metabolizable energy (ME) intake indicated that the maintenance energy requirements of sheep used in this experiment were 310.2 and 302.3 kJ ME/kg body-weight0.75 per d and the values for net utilization of ME for body energy gain were 0.411 and 0.479 with the roughage and concentrate diets respectively..5. It was concluded that the estimated maintenance energy requirements of sheep obtained in this study are realistic values and that the efficiency of utilization of surplus ME for the two diets did not differ significantly.

Estimation of the Maintenance Energy Requirements of Beef Cattle and Lambs

1997 ◽  
Vol 1997 ◽  
pp. 118-118
Author(s):  
R.W.J. Steen ◽  
L.E.R. Dawson ◽  
N. Lavery ◽  
D.E. Kirkpatrick ◽  
S.D. Johnston
Keyword(s):  
Beef Cattle ◽  
Energy Requirement ◽  
Energy Requirements ◽  
Maintenance Energy ◽  
High Fibre ◽  
Energy Retention ◽  
Metabolisable Energy ◽  
Maintenance Energy Requirement ◽  
Using Data ◽  
Gut Metabolism

The maintenance energy requirement of an animal can be defined as the daily metabolisable energy (ME) intake at which it is in zero energy balance. Maintenance energy requirements can be estimated either by measuring fasting metabolism or from a regression relationship between ME intake and energy retention for a number of animals given a range of ME intakes. However maintenance energy requirements may vary according to the composition of the diet, as higher intakes of high-fibre diets have promoted greater rates of gut metabolism than lower intakes of low-fibre diets. In the present study maintenance energy requirements of beef cattle and lambs have been estimated by regressions between ME intake and energy retention using data from a series of studies involving diets based on grass silage or fresh grass and concentrates.

scholarly journals Maintenance energy requirements and forage intake of purebred vs. crossbred beef cows1

2020 ◽  
Vol 4 (2) ◽  
pp. 1182-1195
Author(s):  
Claire E Andresen ◽  
Aksel W Wiseman ◽  
Adam McGee ◽  
Carla Goad ◽  
Andrew P Foote ◽  
...  
Keyword(s):  
Energy Requirement ◽  
Growth Efficiency ◽  
Energy Requirements ◽  
Maintenance Energy ◽  
Calf Growth ◽  
Crossbred Cows ◽  
Breed Type ◽  
Main Effect ◽  
Forage Intake ◽  
Maintenance Energy Requirement

Abstract The objective of this study was to investigate the impacts of cow breed type and age on maintenance requirements, feed energy utilization, and voluntary forage intake. The main effect of breed type included Angus (ANG; n = 32) and Hereford × Angus (HA; n = 27) lactating cows. The main effect of age included 2- and 3-yr-old (YOUNG; n = 29) and 4- to 8-yr-old (MATURE; n = 30) cows. Within breed type and age class, cows were randomly assigned to 1 of 2 pens for a total of 8 pens, each housing 7 to 9 cow/calf pairs. To determine maintenance energy requirements, cows and calves were limit-fed for 105 d to body weight (BW) and body condition score (BCS) stasis. There were no differences between breeds in cow hip height, BW, average milk yield (P > 0.31), diet digestibility, or cow maintenance energy requirement (P = 0.54). Crossbred cows had greater BCS (P < 0.05) throughout the experiment. Efficiency of calf growth was not different between breeds when expressed as feed intake of the cow/calf pair nor as energy intake of the pair per unit of calf BW gain (P ≥ 0.31). Young cows produced less milk per day and per unit of BW0.75 (P < 0.01); however, there was no effect of cow age on maintenance energy requirement, diet digestibility, or efficiency of calf growth (P > 0.10). Subsequently, a 45-d experiment was conducted to determine voluntary low-quality forage intake. Cows were housed in dry-lot pens equipped with shade, windbreaks, and feed bunks with free-choice access to clean water and a chopped hay ration was provided ad libitum to determine forage intake. Daily forage intake was lower (P = 0.05) for HA compared with ANG (123 vs. 132 g/kg BW0.75, respectively) although there was no difference in BW. However, HA cows sustained greater BCS (P < 0.01). There was no difference (P = 0.60) in forage intake per unit of BW0.75 due to cow age. Results indicate similar calf growth efficiency among breed types although crossbred cows maintained greater body energy stores and consumed less low-quality forage during the voluntary intake experiment. These differences could not be attributed to lower maintenance energy requirements. Neither maintenance energy requirement nor calf growth efficiency was different between young and mature cows.

scholarly journals Faecal endogenous loss of calcium in young sheep

1989 ◽  
Vol 61 (1) ◽  
pp. 59-65 ◽  
Author(s):  
J. S. Chrisp ◽  
A. R. Sykes ◽  
N. D. Grace
Keyword(s):  
White Clover ◽  
Dry Matter ◽  
Research Council ◽  
Agricultural Research ◽  
Energy Requirement ◽  
Energy Requirements ◽  
Maintenance Energy ◽  
Agricultural Research Council ◽  
The Mean ◽  
Maintenance Energy Requirement

1. Two groups of eight 6–7-month-old wether lambs were offered either a frozen ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) pasture or a ryegrass-white clover hay, containing 12.1 and 6.4 g calcium/ kg dry matter (DM) respectively. Within groups the amounts offered to individual sheep ranged from 0.5 to 2.0 times the estimated maintenance energy requirements.2. A single intravenous injection of 150 μCi 45Ca as CaCl2. 2H2O, and stable balances were used to determine absorption, faecal endogenous loss and balance of Ca.3. Faecal endogenous loss of Ca increased by 1.2 mg/kg body-weight (W) per d with each g/kg W per d increase in DM intake regardless of the diet. At any DM intake the mean faecal endogenous loss was 5.5 mg/kg W per d higher in the sheep offered the frozen herbage diet when compared with those on the hay diet. At any Ca intake the mean faecal endogenous loss was 6.9 mg/kg W higher in sheep offered the hay diet compared with those on the frozen herbage.4. At feeding levels of about 1.5–2 times the estimated maintenance energy requirement the observed faecal endogenous loss of Ca ranged from 35 to 50 mg/kg W per d, which is two- to threefold greater than the present estimate of the Agricultural Research Council (1980) of 16 mg/kg W per d.5. A simple model to explain the variation in faecal endogenous loss of Ca between the present study with young sheep and that with lactating ewes (Chrisp et al. 1989) also offered herbage diets is developed, which incorporates the concept of a true endogenous loss related to DM intake and a net endogenous loss reflecting the extent of re-absorption of Ca endogenous losses within the gastrointestinal tract.

scholarly journals Energy and nitrogen intake, expenditure and retention at 20° in growing fowl given diets with a wide range of energy and protein contents

1990 ◽  
Vol 64 (3) ◽  
pp. 625-637 ◽  
Author(s):  
M. G. Macleod
Keyword(s):  
Energy Intake ◽  
Energy Requirement ◽  
Metabolizable Energy ◽  
Retention Efficiency ◽  
Protein Nitrogen ◽  
Body Protein ◽  
Wide Range ◽  
Energy Retention ◽  
Maintenance Energy Requirement ◽  
Diet Induced Thermogenesis

Heat production (HP) and the intake and retention of energy and nitrogen were measured at 20° in growing female broiler fowl given diets with metabolizable energy (ME) contents ranging from 8 to 15 MJ/kg at each of two crude protein (nitrogen × 6.25; CP) contents (130 and 210 g/kg). ME intake was partially controlled by the birds, but increased by 30% over the range of dietary ME concentration. CP intake varied directly with dietary CP:ME ratio, indicating that control of energy intake took priority and that food intake did not increase in order to enhance amino acid intake on low-CP diets. Maintenance energy requirement and fasting HP were not affected by diet. Although the HP of fed birds was significantly affected by dietary energy source, there was no evidence for regulatory diet-induced thermogenesis as energy intake increased. Total energy retention doubled on the higher-energy diets as a result of increased intake and retention efficiency in the absence of any compensation by diet-induced thermogenesis. The proportion of energy retained as fat was negatively correlated with dietary CP:ME ratio. It was concluded that the growing female broiler fowl responded to large differences in energy intake and dietary CP concentration not by changes in rate of energy dissipation as heat but by changes in the quantity of energy retained and in the partition of retained energy between body protein and body fat.

scholarly journals 186 The effect of breeding program on cow maintenance requirement and efficiency of calf growth

2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 64-64
Author(s):  
Claire Andresen ◽  
Aksel Wiseman ◽  
Adam McGee ◽  
David Lalman
Keyword(s):  
Milk Production ◽  
Energy Requirement ◽  
Experimental Period ◽  
Biological Efficiency ◽  
Maintenance Energy ◽  
Adaptation Period ◽  
Frame Size ◽  
Calf Growth ◽  
Cow Calf ◽  
Maintenance Energy Requirement

Abstract With genetic tools available today, it is possible to select for traits within breed to achieve similar production phenotypes. Our hypothesis was that biological efficiency of preweaning calf growth would be improved with crossbreeding when dams were selected for similar mature frame size, weight, growth, and milk production. The objective of this study was to determine maintenance energy requirements and efficiency of calf growth through weaning for Angus and Hereford x Angus crossbred cows selected for similar mature BW, growth, and milk production potential. Fifty-nine Angus (n = 32) and Hereford x Angus (n = 27) cow/ calf pairs were assigned to four pen replicates per breed. Cows and calves were limit-fed for a 21-d adaptation period followed by an 84-d experimental period to achieve BW and BCS stasis. Calves did not have access to cow’s feed and daily calf feed allotment was adjusted biweekly to provide 1.25% of previous week’s mean BW. There were no differences due to breed in cow hip height, BW, milk yield (P > 0.31),or cow maintenance energy requirement (P = 0.54). Milk from Hereford-sired cows was slightly more concentrated in energy (P = 0.05) and Hereford-sired cows had greater BCS and ultrasound rib fat and rump fat (P < 0.05) throughout the experiment. Calves from Angus dams were heavier (P 0.01) at the initiation of the experiment, although there were no differences in ADG, final BW, or adjusted weaning BW (P ≥ 0.24). Efficiency of calf growth was not different when expressed as calf BW gain to calf feed and milk energy consumed or as cow/calf pair feed intake or energy intake per unit of calf BW gain (P ≥ 0.31). While the crossbreeding system did not improve biological efficiency of calf growth, more research is necessary to determine if increased cow BCS is advantageous

Simulation of energy metabolism in the simple-stomached animal

1978 ◽  
Vol 39 (2) ◽  
pp. 235-254 ◽  
Author(s):  
A. R. Schulz
Keyword(s):  
Energy Metabolism ◽  
Adenosine Triphosphate ◽  
Metabolic Pathways ◽  
Close Agreement ◽  
Energy Requirement ◽  
Maintenance Energy ◽  
Quasi Steady State ◽  
Computer Programme ◽  
Energy Retention ◽  
Maintenance Energy Requirement

1. A computer programme is described which simulates energy metabolism in the whole animal. Simulation was based on representation of the animal as a quasi-steady-state system.2. Input for the programme consisted of the chemical composition of the diet and an estimate of either the maintenance energy requirement or an estimate of energy retention.3. Simulation was performed by estimating the yield of adenosine triphosphate in the major metabolic pathways operative in simple-stomached animals, and on the utilization of adenosine triphosphate in major anabolic processes.x4. Results obtained from simulation were in close agreement with experimental observations reported by McCracken (1975).

Seasonal changes of metabolism and appetite in Soay rams

1999 ◽  
Vol 69 (1) ◽  
pp. 191-202 ◽  
Author(s):  
C. McG. Argot ◽  
J. S. Smith ◽  
R. N. B. Kay
Keyword(s):  
Seasonal Changes ◽  
Live Weight ◽  
Metabolizable Energy ◽  
Energy Requirements ◽  
Maintenance Energy ◽  
Dietary Energy ◽  
Energy Retention ◽  
Photoperiodic Regime ◽  
Ad Libitum ◽  
Metabolizable Energy Intake

AbstractRelationships between photoperiod and cycles of voluntary food intake (VFI) and maintenance energy requirements (MER) were determined in Soay rams, subjected to a 6-month photoperiodic regime. Food was offered ad libitum (no. = 5) or at a predicted maintenance level (no. = 5). All rams demonstrated 6-month cycles of VFI, growth and reproductive status. Metabolizable energy intake (MEI) was greatest in rams given food ad libitum (666 (s.e. 21.7) kJ/kg metabolic live weight (M0·75) and food-restricted (528 (s.e. 12.2) kJ/kg M0·75) rams during sexual quiescence. Conversely, MEI was minimal (ad libitum, 289 (s.e. 8.4) kJ/kg M0·75; restricted, 428 (s.e. 8.1) kJ/kg M0·75) during the rut. Distinct cycles of heat production (HP) accompanied changes in MEL Changes in HP were similar (P > 0·05) for both groups (ad libitum, 520 (s.e. 22.1) to 394 (s.e. 9.2) kJ/kg M0·75; restricted 503 (s.e. 14.0) to 407 (s.e. 17.5) kJ/kg M0·75) and therefore energy retention varied more (P < 0·015) when rams were given food ad libitum (ad libitum, 131 (s.e. 43-1) to -106 (s.e. 38.2) kJ/kg M0·75; restricted, 78·0 (s.e. 27.1) to -53.0 (s.e. 38.2) kJ/ kg M0·75). Apparent digestibility of dietary energy varied inversely with MEI (P < 0·01). MERs ranged from 524 (s.e. 35.0) kJ/kg M0·75 to 401 (s.e. 27.3) kJ/kg M0·75, a proportional fluctuation of ±0·13. Changes in metabolic rate preceded those in appetite, suggesting a causal relationship.

The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig

1978 ◽  
Vol 40 (3) ◽  
pp. 423-431 ◽  
Author(s):  
W. H. Close ◽  
L. E. Mount ◽  
D. Brown
Keyword(s):  
Environmental Temperature ◽  
Body Weight Gain ◽  
Energy Requirement ◽  
Metabolizable Energy ◽  
Growing Pig ◽  
Body Weights ◽  
Energy Retention ◽  
Four Levels ◽  
Maintenance Energy Requirement ◽  
Environmental Temperatures

1. Measurements of energy and nitrogen balances were made on thirty-eight individually housed pigs (initial body-weights 21–38 kg) at environmental temperatures of 10, 15, 20, 25 and 30° with four levels of feeding at each temperature. Values for energy retention (ER), protein (P) and fat (F) deposition and body weight gain (δW) were calculated at each temperature at metabolizable energy (me) intakes equivalent to once (M; 440 kJ/kg0.75 per d), twice (2M), three (3M) and four (4M) times the thermoneutral maintenance energy requirement.2. ER at each plane of nutrition increased with temperature to maximal values between approximately 20 and 25° ER was negative at four of the five environmental temperatures at M.3. P increased significantly with increase in me intake but was dependent on environmental temperatures only at intakes of M and 2M. The increase in P per unit increment in me intake decreased from 0.16 at 10° to 0.12 at 30°. The net efficiency of protein utilization also decreased with increase in environmental temperature from 0.54 at 10° to 0.39 at 30°.4. F increased significantly with increase in me intake, but was more temperature-dependent than P, increasing to maximum values estimated to be between 20 and 25° at each level of intake; F at 30° was less than that at 25°. The increase in F per unit increment in me intake decreased from 0.63 at 10° to 0.51 at 30°.5. The optimum temperature for ΔW was dependent upon me intake, varying from above 30° at M to less than 20° at 4M. The reduction in ΔW per 1° at 15° was also dependent upon the level of intake decreasing from 1.63 g/kg0.75 per d at M to -0.09 at 4M.6. For a 35 kg pig the reduction in P, as a result of a 1° decrease in temperature at 15° at an intake corresponding to 2.5M, was equivalent to a 4 g/d reduction in food intake; the corresponding equivalent for F was 28 g/d.

scholarly journals The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig

1978 ◽  
Vol 40 (3) ◽  
pp. 413-421 ◽  
Author(s):  
W. H. Close ◽  
L. E. Mount
Keyword(s):  
Critical Temperature ◽  
Heat Loss ◽  
Energy Requirement ◽  
Metabolizable Energy ◽  
Maintenance Energy ◽  
Growing Pig ◽  
Extra Food ◽  
Four Levels ◽  
Maintenance Energy Requirement ◽  
Energy Balances

1. The heat losses and energy balances of thirty-eight individually housed pigs (initial body-weights 21–38 kg) were measured continuously for periods of 14 d when they were maintained at environmental temperatures of 10, 15, 20, 25 or 30°. At each temperature four levels of feeding were given approximating to once, twice and three times the maintenance energy intake and the ad lib. level. The minimal maintenance energy requirement (M) was calculated to be 440 kJ metabolizable energy (me)/kg0.75 per d at 25°.2. me intake at the ad lib. level decreased from 1965 kJ/kg0.75 per d at 10° to 1202 at 30°.3. Heat loss calculated from multiple regression analysis decreased to minimum levels between 20 and 25° 30° was within the hyperthermic zone at each plane of nutrition.4. The partition of heat loss into its sensible and evaporative components showed that evaporation increased from 25% at 10° to 78% at 30°.5. Critical temperature was dependent upon food intake and decreased from 23.1° at M to 20.7° at 2M, 18.0° at 3M and 16.7° at 4M.6. The extra food required to meet extra thermoregulatory heat production per 1° below the effective critical temperature was 0.65 g/kg body-weight per d.

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