EVALUATION OF PROTEIN IN FOODS: VII. FACTORS INFLUENCING NET PROTEIN UTILIZATION AS DETERMINED BY CARCASS ANALYSIS

1962 ◽  
Vol 40 (1) ◽  
pp. 1663-1670
Author(s):  
A. B. Morrison ◽  
Z. I. Sabry ◽  
J. A. Campbell
Keyword(s):  
Direct Relationship ◽  
Nitrogen Retention ◽  
Analysis Data ◽  
Male Rats ◽  
Lysine Content ◽  
Control Groups ◽  
Protein Utilization ◽  
Protein Levels ◽  
Factors Influencing ◽  
Net Protein

The effects of deficiency of vitamins and minerals on net protein utilization (N.P.U.) values obtained with casein at various protein levels were studied in growing male rats. Animals given diets without added vitamins and minerals lost weight and had reduced N.P.U. values. Carcass analysis data indicated that nitrogen retention occurred in these animals concomitantly with loss of body water and fat. In further studies, a direct relationship was observed between N.P.U. values and the dietary lysine content, at lysine concentrations varying from 0.32 to 0.72%. The use of various control groups to estimate endogenous and metabolic nitrogen losses gave similar N.P.U. values.

EVALUATION OF PROTEIN IN FOODS: VII. FACTORS INFLUENCING NET PROTEIN UTILIZATION AS DETERMINED BY CARCASS ANALYSIS

1962 ◽  
Vol 40 (12) ◽  
pp. 1663-1670 ◽  
Author(s):  
A. B. Morrison ◽  
Z. I. Sabry ◽  
J. A. Campbell
Keyword(s):  
Direct Relationship ◽  
Nitrogen Retention ◽  
Analysis Data ◽  
Male Rats ◽  
Lysine Content ◽  
Control Groups ◽  
Protein Utilization ◽  
Protein Levels ◽  
Factors Influencing ◽  
Net Protein

The effects of deficiency of vitamins and minerals on net protein utilization (N.P.U.) values obtained with casein at various protein levels were studied in growing male rats. Animals given diets without added vitamins and minerals lost weight and had reduced N.P.U. values. Carcass analysis data indicated that nitrogen retention occurred in these animals concomitantly with loss of body water and fat. In further studies, a direct relationship was observed between N.P.U. values and the dietary lysine content, at lysine concentrations varying from 0.32 to 0.72%. The use of various control groups to estimate endogenous and metabolic nitrogen losses gave similar N.P.U. values.

scholarly journals Nitrogen balance of starting barrow pigs fed on increasing lysine levels

2004 ◽  
Vol 47 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Ivan Moreira ◽  
Alessandro Luis Fraga ◽  
Diovani Paiano ◽  
Gisele Cristina de Oliveira ◽  
Cláudio Scapinello ◽  
...  
Keyword(s):  
Nitrogen Balance ◽  
Nitrogen Retention ◽  
Nitrogen Excretion ◽  
Protein Utilization ◽  
Urea Nitrogen ◽  
Plasma Urea ◽  
Low Protein ◽  
Feed Protein ◽  
Protein Diets ◽  
Net Protein

The effects of increasing lysine levels on nitrogen balance of pigs fed on low protein diets were evaluated. Four treatments (diets) containing lysine levels (0.8, 1.0 1.2 and 1.4%) were applied to 12 starting (20.0 ± 1.8 kg) barrow pigs. Methionine, threonine and tryptophan were kept constant to the lysine ratio in all diets. Feces and urine were collected during a 5-day period. Nitrogen output in urine (NOU), total nitrogen output (TNO), nitrogen retention (NR), net protein utilization (NPU), biological value or feed protein (BVFP), urine urea nitrogen (UUN), and plasma urea nitrogen (PUN) were determined. PUN showed high negative correlations with BVFP (-0.84), NPU (-0.76), and NR (-0.78) and a positive correlation (0.79) to NOU. Lowest nitrogen excretion and the best use of diet protein were obtained with 1.1% total lysine level. PUN is efficient to indicate amino acid for pigs.

THE METABOLISM OF NITROGEN AND THE DIGESTIBILITY COEFFICIENT AND BIOLOGICAL VALUE OF THE PROTEINS AND NET PROTEIN UTILIZATION IN POOR RICE DIET SUPPLEMENTED WITH METHIONINE-FORTIFIED SOYA FLOUR OR SKIM MILK POWDER

1964 ◽  
Vol 42 (5) ◽  
pp. 641-650 ◽  
Author(s):  
Myna Panemangalore ◽  
H. N. Parthasarathy ◽  
Kantha Joseph ◽  
A. N. Sankaran ◽  
M. Narayana Rao ◽  
...  
Keyword(s):  
Milk Powder ◽  
Skim Milk ◽  
Nitrogen Retention ◽  
Skim Milk Powder ◽  
Protein Supplement ◽  
Soya Flour ◽  
Protein Utilization ◽  
Biological Value ◽  
Net Protein ◽  
Rice Diet

The effect of supplementing a poor rice diet commonly used in India with methionine-fortified soya flour or skim milk powder was studied in seven girls aged 8–9 years, using as criteria: the retention of nitrogen, digestibility coefficient, biological value, and net protein utilization of the proteins. The retention of nitrogen on the rice diet was very low (20.3 mg/kg day). Supplementation of the rice diet with soya flour, methionine-fortified soya flour or skim milk powder, so as to provide about 1 g/kg extra protein, made up the protein deficiency in the rice diet and resulted in a significant increase in nitrogen retention (95.6, 112.1, and 113.6 mg/kg day). The retention of nitrogen on the rice diet supplemented with methionine-fortified soya flour (112.1 mg/kg day) or skim milk powder (113.6 mg/kg day) was nearly the same and significantly higher than that (95.6 mg/kg day) observed with a diet supplemented with soya flour. The biological value and net protein utilization of the mixed proteins of rice – skim milk powder diet and rice–methionine-fortified soya flour diet (62.4 and 62.2 and 53.3 and 54.0 respectively) were nearly the same and significantly higher than those (58.3 and 49.9) of rice – soya flour diet. The results show that methionine-fortified soya flour is almost as good as skim milk powder and significantly superior to soya flour as a protein supplement to rice diet.

scholarly journals Nitrogen retention in the pig

1977 ◽  
Vol 37 (2) ◽  
pp. 143-155 ◽  
Author(s):  
J. R. Carr ◽  
K. N. Boorman ◽  
D. J. A. Cole
Keyword(s):  
Body Weight ◽  
Regression Analysis ◽  
Nitrogen Retention ◽  
N Losses ◽  
Protein Utilization ◽  
N Retention ◽  
Protein Requirements ◽  
Gross Efficiency ◽  
N Utilization ◽  
Net Protein

1. Published results have been used to study the relationships between nitrogen retention (NR), body-weight (W) and N intake in the pig.2. The general decrease in maximal NR (g/d per kg W0.75) with increasing W (kg) was curvilinear for values of W from 1.5 to 45: NR = 3.324−0.098 W+0.001 W2; and rectilinear for values of W from 45 to 165: NR = 1.252−0.006 W. Values for protein requirements derived from these equations agreed closely with published estimates.3. The slopes of the curves for NR (g/d per kg W0.75) v. N intake (g/d) decreased as W (kg) increased from about 2.5 to 190. After extrapolation to a proposed common intercept on the NR axis of -150 mg N/d per kg W0.75, regression analysis of the intercepts of these curves on the N-intake axis v. W gave an estimate of N requirements for maintenance of 246±19 mg/d per kg W0.75.4. The results also indicated that at low N intakes net protein utilization (N retention+ total obligatory N losses ÷ N intake) was essentially independent of W, whereas the gross efficiency of N utilization (NR ÷ N intake) was influenced by both W and N intake.

scholarly journals Digestible protein requirements for maintenance, growth, and efficiency of protein utilization in pacu (Piaractus mesopotamicus) juveniles: an exponential nitrogen utilization model

2021 ◽  
Vol 49 (4) ◽  
pp. 608-619
Author(s):  
Cleber F.M. Mansano ◽  
Edney P. Da Silva ◽  
Kifayat U. Khan ◽  
Beatrice I. Macente ◽  
Thiago M.T. Nascimento ◽  
...  
Keyword(s):  
Nitrogen Retention ◽  
Model Parameters ◽  
Protein Utilization ◽  
Piaractus Mesopotamicus ◽  
Protein Requirements ◽  
Protein Levels ◽  
Randomized Design ◽  
Acclimation Period ◽  
Digestible Protein ◽  
The Relationship

The present study aimed to estimate digestible protein (DP) requirements for maintenance and growth and assess the efficiency of protein utilization in pacu (Piaractus mesopotamicus) juveniles. A complete randomized design consisted of seven treatments, and five replicates (tanks) per treatment was used. After a one-week acclimation period, 350 pacu juveniles of 27.48 ± 1.8 g (initial average body weight - BW) were equally distributed among 35 tanks (10 fish per tank) of 450 L. Fish were fed with seven graded digestible protein levels (64.5, 111.8, 164.6, 217.1, 264.4, 316.2 and 369.5 g kg-1) three times a day until apparent satiation for 120 days. The monomolecular model parameters including nitrogen maintenance requirement (NMR) (37.76 mg BW0.67 kg-1 d-1), daily nitrogen deposition (ND) (194.8 mg BW0.67 kg-1 d-1), and protein intakes (based on metabolic BW) of 1638, 1902, and 2241 mg kg-1BW0.67 d-1 for 75, 80 and 85% maximum theoretical nitrogen retention (NRmaxT), respectively and the efficiency of protein utilization (529×10-6) were estimated through the relationship between nitrogen intake (NI) and ND. The digestible protein requirements for 75, 80, and 85% of NRmaxT were estimated as 187, 217, and 256 g kg-1 respectively by the monomolecular model based on the daily feed intake of 2% of live BW of pacu juveniles.

The effect of pyridoxine supplementation on dietary protein utilization in gilthead seabream fry

1995 ◽  
Vol 60 (1) ◽  
pp. 157-162 ◽  
Author(s):  
R. T. M. Baker ◽  
S. J. Davies
Keyword(s):  
Sparus Aurata ◽  
Gilthead Seabream ◽  
Feeding Trial ◽  
Protein Utilization ◽  
Protein Levels ◽  
Low Protein ◽  
Sparing Effect ◽  
Dietary Protein Utilization ◽  
Protein Diets ◽  
Net Protein

A study was undertaken to ascertain the effect of pyridoxine in diets of varying protein to energy ratio (P: E) for Mediterranean gilthead seabream fry (Sparus aurata) with respect to protein utilization. Diets were formulated to provide three levels of added pyridoxine (0·5, 5·0 and 50·0 mg/kg), at two protein levels (320 or 470 g/kg) whilst maintaining a similar gross isocalorific profile at 20 MJ/kg. Feeding level was proportionately 0·02 of the fish body weight per day, resulting in the following effects after a 70-day feeding trial. Low P: E ratio diets (15 g/MJ) did not perform as well as high P: E diets (24 g/MJ), with respect to growth related indices. Higher inclusions of pyridoxine into diets of equal P: E ratios, caused elevations in food conversion efficiency, protein efficiency ratio and apparent net protein utilization. A marked improvement of growth rate concomitant with pyridoxine level only occurred in the high P: E diets. It was concluded that incremental additions of pyridoxine in the diet, increased the efficiency of protein utilization for all diets tested. However, the protein sparing effect oflipid was not achieved for the low protein diets indicating the relatively high requirement for protein in the growth of the juvenile seabream.

Conjugated Linoleic Acid Causes a Marked Increase in Liver α-Tocopherol and Liver α-Tocopherol Transfer Protein in C57BL/6 J Mice

2010 ◽  
Vol 80 (1) ◽  
pp. 65-73 ◽  
Author(s):  
Pei-Min Chao ◽  
Wan-Hsuan Chen ◽  
Chun-Huei Liao ◽  
Huey-Mei Shaw
Keyword(s):  
Antioxidant Enzymes ◽  
Linoleic Acid ◽  
Conjugated Linoleic Acid ◽  
Thiobarbituric Acid ◽  
Control Group ◽  
Thiobarbituric Acid Reactive Substances ◽  
Control Groups ◽  
Protein Levels ◽  
Transfer Protein ◽  
And Control

Conjugated linoleic acid (CLA) is a collective term for the positional and geometric isomers of a conjugated diene of linoleic acid (C18:2, n-6). The aims of the present study were to evaluate whether levels of hepatic α-tocopherol, α-tocopherol transfer protein (α-TTP), and antioxidant enzymes in mice were affected by a CLA-supplemented diet. C57BL/6 J mice were divided into the CLA and control groups, which were fed, respectively, a 5 % fat diet with or without 1 g/100 g of CLA (1:1 mixture of cis-9, trans-11 and trans-10, cis-12) for four weeks. α-Tocopherol levels in plasma and liver were significantly higher in the CLA group than in the control group. Liver α-TTP levels were also significantly increased in the CLA group, the α-TTP/β-actin ratio being 2.5-fold higher than that in control mice (p<0.01). Thiobarbituric acid-reactive substances were significantly decreased in the CLA group (p<0.01). There were no significant differences between the two groups in levels of three antioxidant enzymes (superoxide dismutase, glutathione peroxidase, and catalase). The accumulation of liver α-tocopherol seen with the CLA diet can be attributed to the antioxidant potential of CLA and the ability of α-TTP induction. The lack of changes in antioxidant enzyme protein levels and the reduced lipid peroxidation in the liver of CLA mice are due to α-tocopherol accumulation.

scholarly journals Obligatory Nitrogen Losses in Pregnant Rats with Special Reference to Estimation of Net Protein Utilization.

1992 ◽  
Vol 38 (5) ◽  
pp. 493-499
Author(s):  
Sadaichi SAKAMOTO ◽  
Masahiro MORI ◽  
Masaharu OHNAKA ◽  
Yoshiaki NIIYAMA
Keyword(s):  
Special Reference ◽  
Nitrogen Losses ◽  
Pregnant Rats ◽  
Protein Utilization ◽  
Net Protein

Abstract 15295: Molecular Mechanism of Chronic Sildenafil-Caused Regression of Heart Failure: Effects on the Express of Cardiac SR Ca2+-ATPase, Subtype of β-Adrenergic Receptors and Nitric Oxide Synthase Isoforms

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Heng-Jie Cheng ◽  
Tiankai Li ◽  
Che Ping Cheng
Keyword(s):  
Nitric Oxide ◽  
Heart Failure ◽  
Nitric Oxide Synthase ◽  
Adrenergic Receptors ◽  
Left Ventricular ◽  
Male Rats ◽  
Protein Levels ◽  
Myocyte Function ◽  
Oxide Synthase ◽  
Β Adrenergic Receptors

Background: Sildenafil (SIL), a selective inhibitor of PDE5 has been shown to exert profound beneficial effects in heart failure (HF). Recently we further found that SIL caused regression of cardiac dysfunction in a rat model with isoproterenol (ISO)-induced progressive HF. However, the molecular basis is unclear. We hypothesized that reversal of HF-induced detrimental alterations on the expressions of cardiac SR Ca 2+ -ATPase (SERCA2a), β-adrenergic receptors (AR) and nitric oxide synthase (NOS) isoforms by SIL may play a key role for its salutary role in HF. Methods: Left ventricular (LV) and myocyte function and the protein levels of myocyte β 1 - and β 3 - AR, SERCA2a, phospholamban (PLB) and three NOS were simultaneously evaluated in 3 groups of male rats (6/group): HF , 3 months (M) after receiving ISO (170 mg/kg sq for 2 days); HF/SIL , 2 M after receiving ISO, SIL (70 μg/kg/day sq via mini pump) was initiated and given for 1 M; and Controls (C). Results: Compared with controls, ISO-treated rats progressed to severe HF at 3 M after ISO followed by significantly decreased LV contractility (E ES , HF: 0.7 vs C: 1.2 mmHg/μl) and slowed LV relaxation, reductions in the peak velocity of myocyte shortening (77 vs 136 μm/sec), relengthening (62 vs 104 μm/sec) and [Ca 2+ ] iT (0.15 vs 0.24) accompanied by a diminished myocyte inotropic response to β-AR agonist, ISO (10 -8 M). These abnormalities were associated with concomitant significant decreases in myocyte protein levels of β 1 -AR (0.23 vs 0.64), SERCA2a (0.46 vs 0.80), PLB Ser16 /PLB ratio (0.24 vs 0.40) and eNOS (0.28 vs 0.46), but significantly increases in protein levels of β 3 -AR (0.29 vs 0.10) and iNOS (0.18 vs 0.08) with relatively unchanged nNOS. Chronic SIL prevented the HF-induced decreases in LV and myocyte contraction, relaxation, peak [Ca 2+ ] iT , and restored normal myocyte contractile response to ISO stimulation. With SIL, protein levels of myocyte β 1 - and β 3 -AR, SERCA2a were restored close to control values, but eNOS was significantly elevated than controls (0.77). Conclusions: Chronic SIL prevents HF-caused downregulation of cardiac β 1 -AR and reverse contrast changes between iNOS and β 3 -AR with SERCA 2a and eNOS expression, leading to the preservation of LV and myocyte function, [Ca 2+ ] iT , and β-adrenergic reserve.

Sign in / Sign up

Export Citation Format

Share Document