Foliage of Eucalyptus-Punctata and the Maintenance Nitrogen Requirements of Koalas, Phascolarctos-Cinereus

1986 ◽  
Vol 34 (1) ◽  
pp. 17 ◽  
Author(s):  
SJ Cork
Keyword(s):  
Metabolic Rate ◽  
Standard Metabolic Rate ◽  
Nitrogen Excretion ◽  
Staple Food ◽  
Phascolarctos Cinereus ◽  
Microbial Nitrogen ◽  
Faecal Nitrogen ◽  
Feeding Trials ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Nitrogen metabolism and balance were investigated in captive koalas fed mature foliage of a staple food tree, Eucalyptus punctata, in six feeding trials at various times of year. Winter foliage contained less nitrogen than summer foliage but koalas compensated by eating more in winter. Thus, nitrogen balance did not differ significantly between seasons. Urinary nitrogen excretion similarly showed no seasonal trend but losses of non-dietary (i.e. endogenous and microbial) faecal nitrogen were greater in winter than in summer, presumably because of the higher food intake. Estimates of the requirements of dietary and truly digestible nitrogen for maintenance of nitrogen equilibrium (283 mg . kg-0.75 . d-� and 271 mg . kg-0.75 . d-� respectively) were comparable with several estimates for other marsupials. Although urinary nitrogen.excretion by koalas was low compared with that by other marsupials, consistent with the koala's standard metabolic rate, losses of non-dietary faecal nitrogen were relatively high. It was concluded that relatively high losses of endogenous andlor microbial nitrogen in faeces are a consequence of feeding on Eucalyptus foliage and that the koala's low standard metabolic rate is an important adaptation permitting it to utilize this diet by partly compensating for faecal nitrogen losses.

Studies on marsupial nutrition V. the nitrogen requirements of the euro, Macropus robustus

1967 ◽  
Vol 15 (1) ◽  
pp. 7 ◽  
Author(s):  
GD Brown ◽  
A.R. Main
Keyword(s):  
Dry Matter ◽  
Arid Environment ◽  
Nitrogen Excretion ◽  
Dry Matter Intake ◽  
Dietary Nitrogen ◽  
Faecal Nitrogen ◽  
Feeding Trials ◽  
Comparison Of The Results ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

The nitrogen requirements of some female euros (Macropus robustus) were determined by means of nitrogen balance feeding trials. The average minimum dietary nitrogen requirement for the maintenance of nitrogen equilibrium was 1.99 g/day or 309 mg/day per kgW*0.73. The metabolic faecal nitrogen output of the euros, determined indirectly, was estimated to be 0.27 g/100 g dry matter intake. The minimum digestible nitrogen requirements of the euros were 160 mg/day per kgW*0.73, equivalent to approximately 1 g digestible nitrogen per day. The minimum urinary nitrogen excretion of the euros, at dietary nitrogen intakes of approximately 1 g/day, was an average of 34 mg/day per kgW*0.73. Comparison of the results obtained with data for eutherian species reported in the literature indicates that the nitrogen requirements and urinary nitrogen excretion of this species is markedly less than that of eutherian species. The results are briefly discussed in relation to survival of the euro in the arid environment of the Pilbara district of Western Australia.

Studies on marsupial nutrition. VI. The utilization of dietry urea by the Euro or Hill Kangaroo, Macropus robustus (Gould)

1969 ◽  
Vol 17 (2) ◽  
pp. 187 ◽  
Author(s):  
GD Brown
Keyword(s):  
Nitrogen Balance ◽  
Dietary Protein ◽  
Nitrogen Retention ◽  
Nitrogen Excretion ◽  
Microbial Protein ◽  
Digestive Physiology ◽  
Protein Nitrogen ◽  
Feeding Trials ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Macropod marsupials, the kangaroos and wallabies, are characterized by a ruminant-like digestive physiology. One feature of digestion in eutherian species of ruminants is the ability of these animals to utilize non-protein nitrogen through the conversion of such nitrogen to microbial protein by the microorganisms in the rumen. In the present experiments with the euro or hill kangaroo (M. robustus), the utilization of dietary protein (casein) and non-protein nitrogen (urea) has been compared by means of nitrogen balance feeding trials. No consistent differences between the levels of nitrogen retention and urinary nitrogen excretion were observed for euros fed rations supplemented with either casein or urea. It is suggested that the digestion of nitrogen by the ruminant-like macropod marsupials is similar to that of eutherian species of ruminant herbivores.

scholarly journals Feasibility of achieving different protein targets using a hypocaloric high-protein enteral formula in critically ill patients

Critical Care ◽  
2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Pierre Singer ◽  
Itai Bendavid ◽  
Ilana BenArie ◽  
Liran Stadlander ◽  
Ilya Kagan
Keyword(s):  
Critically Ill ◽  
Nitrogen Balance ◽  
High Protein ◽  
Nitrogen Excretion ◽  
Protein Targets ◽  
Protein Target ◽  
Group A ◽  
Group B ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Abstract Background and aims Combining energy and protein targets during the acute phase of critical illness is challenging. Energy should be provided progressively to reach targets while avoiding overfeeding and ensuring sufficient protein provision. This prospective observational study evaluated the feasibility of achieving protein targets guided by 24-h urinary nitrogen excretion while avoiding overfeeding when administering a high protein-to-energy ratio enteral nutrition (EN) formula. Methods Critically ill adult mechanically ventilated patients with an APACHE II score > 15, SOFA > 4 and without gastrointestinal dysfunction received EN with hypocaloric content for 7 days. Protein need was determined by 24-h urinary nitrogen excretion, up to 1.2 g/kg (Group A, N = 10) or up to 1.5 g/kg (Group B, N = 22). Variables assessed included nitrogen intake, excretion, balance; resting energy expenditure (REE); phase angle (PhA); gastrointestinal tolerance of EN. Results Demographic characteristics of groups were similar. Protein target was achieved using urinary nitrogen excretion measurements. Nitrogen balance worsened in Group A but improved in Group B. Daily protein and calorie intake and balance were significantly increased in Group B compared to Group A. REE was correlated to PhA measurements. Gastric tolerance of EN was good. Conclusions Achieving the protein target using urinary nitrogen loss up to 1.5 g/kg/day was feasible in this hypercatabolic population. Reaching a higher protein and calorie target did not induce higher nitrogen excretion and was associated with improved nitrogen balance and a better energy intake without overfeeding. PhA appears to be related to REE and may reflect metabolism level, suggestive of a new phenotype for nutritional status. Trial registration 0795-18-RMC.

Effect of starch on the utilization by sheep of a straw diet supplemented with urea and minerals

1976 ◽  
Vol 27 (1) ◽  
pp. 139 ◽  
Author(s):  
JG Mulholland ◽  
JB Coombe ◽  
WR McManus
Keyword(s):  
Organic Matter ◽  
Nitrogen Retention ◽  
Nitrogen Excretion ◽  
Digestible Organic Matter ◽  
Cellulose Digestibility ◽  
Oat Straw ◽  
Total Body ◽  
Body Energy ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

Individually penned Border Leicester x Merino wethers, aged 11 months, were fed ad lib. for 16 weeks on a basal ration of ground, pelleted oat straw, urea and minerals, supplemented with 0, 5, 10, 15, 20, 30 or 40% starch. The diets contained equal percentages of nitrogen and minerals. Dry matter intake reached a maximum of 2000 g/day with 30% starch; above this starch level, digestive disturbances were observed. Organic matter digestibility was increased by the addition of starch, but cellulose digestibility was depressed by as much as 18 units with the addition of 30% starch. Up to 10% the starch level had little effect on cellulose digestibility. Liveweight change was significantly correlated with digestible organic matter intake, mean daily weight gains varying from 22 g with no starch to 104 g with 30% starch. However, a large percentage of the liveweight gain was as total body water, and body energy storage increased appreciably only when the diet contained at least 20% starch. The inclusion of 5% starch slightly depressed both intake and liveweight gain. Daily clean wool production was significantly increased at starch levels higher than 20% and ranged from 5.3 to 7.5 g/day with 0 and 40% starch respectively. Increasing levels of starch had little effect on apparent nitrogen digestibility, but resulted in a substantial increase in nitrogen retention through a reduction in urinary nitrogen excretion. Serum urea levels fell from a mean of 42 mg/100 ml during the first week to 31 mg/100 ml during subsequent periods, with no significant differences between diets. With the general exception of potassium, mineral balances were positive or close to zero throughout the experiment.

Branched-Chain Amino Acids, Nitrogen Excretion and Injury in Man

1976 ◽  
Vol 50 (5) ◽  
pp. 393-399 ◽  
Author(s):  
J. H. Wedge ◽  
R. De Campos ◽  
A. Kerr ◽  
R. Smith ◽  
Rose Farrell ◽  
...  
Keyword(s):  
Amino Acids ◽  
Venous Blood ◽  
Branched Chain Amino Acids ◽  
Nitrogen Excretion ◽  
Adult Males ◽  
Blood Concentrations ◽  
Branched Chain ◽  
Injured Patients ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen

1. Venous blood concentrations of the branched-chain amino acids, valine, leucine and isoleucine, and urinary nitrogen excretion have been measured in sixteen adult males, from 2 h to 7 days after injury, and in four adults after elective skin grafts. 2. In the injured group the concentrations of these amino acids rose significantly 24 h after injury and had doubled at 4 days and remained high; in contrast the skin-graft patients showed no significant change. 3. In those injured patients with initial hyperketonaemia, defined as more than 0·2 mmol/l, the increase in concentrations of branched-chain amino acids at the fourth and seventh days after injury was significantly less than in those with normoketonaemia, and was accompanied by lower urinary nitrogen excretion throughout the whole period. 4. It is suggested that the changes in the concentration of branched-chain amino acids after injury indicate decreased uptake by muscle or excessive release due to an imbalance between protein synthesis and protein catabolism in this tissue.

scholarly journals Endogenous Losses of Nitrogen and Protein Requirement for Maintenance of Sheep

2021 ◽  
Vol 3 (2) ◽  
pp. 156-162
Author(s):  
T. A. Adegbola ◽  
A. U. Mba ◽  
F. O. Olubajo
Keyword(s):  
West African ◽  
Water Soluble ◽  
Soluble Nitrogen ◽  
N Losses ◽  
Faecal Nitrogen ◽  
Feeding Trials ◽  
Endogenous Urinary Nitrogen ◽  
Protein Supply ◽  
Urinary Nitrogen ◽  
Dwarf Sheep

FOUR fistulated and four intact West African dwarf Sheep, maintained on hay and concentrate supplements were used for a study of metabolic faecal nitrogen (MEN) endogenous urinary nitrogen (EUN). The composition of the faecal losses was examined. The values obtained enabled calculation of nitrogen requirement of the sheep for maintenance, as well as the value of the experimental rations in the nutrition of the sheep. Values of MFN obtained by two methods were 3.31 and 3.10 g/kg Dry matter (DM) intake. Endogenous urinary nitrogen value was 0.024 g/day per metabolic weight (Wkg0.75.) Analysis of the faeces of the sheep showed that 21.1% of faecal nitrogen (N) were present as microbial and endogenous nitrogen (MEN) and 17.3% was present as water-soluble nitrogen. The biological values (BV) of the rations ranged from 85.7% to 100.0% and the digestibility for maintenance, were 1.20 and 0.41 g/day/Wkg 0.75 during the feeding trials. Values obtained for endogenous N losses and N requirement for low maintenance were low compared with reported values and this may indicate adaptation of the dwarf sheep for survival under inadequate dietary protein supply.

Urinary nitrogen excretion at the early stage of severe acute pancreatitis

2020 ◽  
Vol 21 (4) ◽  
pp. 131-134
Author(s):  
O. G. Sivkov ◽  
◽  
A. O. Sivkov ◽  
Keyword(s):  
Acute Pancreatitis ◽  
Severe Acute Pancreatitis ◽  
Early Stage ◽  
Ideal Body Weight ◽  
Nitrogen Excretion ◽  
The Third ◽  
Ideal Body ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen ◽  
The Ideal

Aim. To study urinary nitrogen excretion at the early stage of severe acute pancreatitis. Materials and methods. Prospective, single-center, cohort study. Inclusion criteria: diagnosis of acute pancreatitis and presence of at least one of the predictors of severe course. Among all patients (n = 72), a cohort of patients with severe acute pancreatitis (n = 32) was allocated. Three groups were formed in it: the first one – all patients, the second one – survivors (n = 24), the third one – deceased (n = 8). Urinary nitrogen excretion was determined using the Deacon formula. Measurements were performed on the first, third and fifth days of the disease. Statistical processing of the material was carried out by the SPSS software package. The null hypothesis was rejected at p < 0.05. Results. In the first week of the disease in all groups, the maximum urinary nitrogen excretion occurs on the 3rd day. When comparing the results of the second and third groups, it was found that the urinary nitrogen excretion on the first and fifth days did not have a statistically significant difference between the groups (respectively, p = 0.138, p = 0.572), and the results of the third day have (p = 0.014). A similar pattern remains when recalculating the nitrogen loss in the urine to the ideal weight; for the third day, the differences between the second and third groups were statistically significant (p = 0.007). ROC analysis of urinary nitrogen excretion of the third day calculated to the ideal body weight showed an area under the curve of 0.813 (p < 0.009). The value at the cut-off point is defined as 0.65 g/kg/day. The sensitivity of the model was 0.75%, specificity – 0.83%. Conclusion. If in a patient with acute pancreatitis, there is urinary nitrogen excretion on the third day from the onset of the disease, calculated to an ideal body weight of ≥ 0.65 g/kg/day, an unfavorable outcome of the disease is predicted.

The effect of ERDP:FME ratio and DUP supply from concentrates on the performance of lactating ewes offered grazed grass

1996 ◽  
Vol 1996 ◽  
pp. 160-160
Author(s):  
R.G. Wilkinson ◽  
L.A. Sinclair ◽  
J. Powles ◽  
C.M. Minter
Keyword(s):  
Crude Protein ◽  
Microbial Growth ◽  
High Rate ◽  
Nitrogen Excretion ◽  
Crude Protein Content ◽  
Nitrogen Utilisation ◽  
Metabolisable Energy ◽  
Urinary Nitrogen Excretion ◽  
Urinary Nitrogen ◽  
Degradable Protein

Fresh grass is a highly variable product, which is generally characterised as having a high crude protein content, with a high rate and extent of degradation in the rumen. For lactating ruminants, this may result in an effective rumen degradable protein: fermentable metabolisable energy (ERDP:FME) ratio in excess of the optimum requirement for microbial growth, leading to inefficient nitrogen utilisation and high levels of urinary nitrogen excretion. One method of improving the efficiency of nitrogen utilisation is the use of supplements. An appropriate supplement should optimise ERDP and FME supply to the rumen and provide sufficient metabolisable protein (MP) to balance animal requirements. The objective of the experiment was to investigate the response of lactating ewes offered grazed grass to variations in ERDP:FME ratio and digestible undegradable protein (DUP) supply from concentrate supplements.

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