Protein utilization in rats receiving a low-protein diet with various limiting amino acids

1978 ◽  
Vol 39 (1) ◽  
pp. 13-18 ◽  
Author(s):  
H. Rafalski ◽  
E. JabŁOŃski ◽  
Teresa Switoniak
Keyword(s):  
Amino Acids ◽  
Protein Utilization ◽  
Low Protein ◽  
Chemical Score ◽  
Amino Acid Score ◽  
Maize Protein ◽  
Low Levels ◽  
Limiting Amino Acids ◽  
Protein Diets ◽  
Net Protein

1. A study was made of protein utilization in rats given a variety of low-protein diets containing (g/kg) egg albumin 18, casein 49, gluten 50, or mixtures of either maize protein and gelatine 58, or casein and gelatin 37, each with supplemental methionine. The diets were limiting in leucine, tryptophan or lysine, or in both tryptophan and the sulphur-containing amino acids.2. Values obtained for net protein utilization (npu) at these low levels of nitrogen intake were markedly higher than the amino acid score calculated for the different test proteins, except with casein for which the two values were similar. The npu values agreed more closely with chemical score values based on the content of S-amino acids or isoleucine in the dietary protein.

The use of hydroxyproline analyses to predict the nutritional value of the protein in different animal tissues

1972 ◽  
Vol 27 (3) ◽  
pp. 475-481 ◽  
Author(s):  
Z. Dvořák
Keyword(s):  
Amino Acids ◽  
Nutritional Value ◽  
Amino Acid Content ◽  
Close Correlation ◽  
Regression Equations ◽  
Animal Tissues ◽  
Chemical Score ◽  
Limiting Amino Acids ◽  
Net Protein ◽  
Total Amino Acids

1. The amounts of available cystine and tyrosine in the protein of different animal tissues showed a close correlation with the level of hydroxyproline, and may be estimated from hydroxyproline values by regression equations.2. Estimates of ‘chemical score’ have been calculated from the content of hydroxyproline determined in a series of samples for which net protein utilization (NPU) for rats had also been determined. Chemical scores calculated as percentages of the total ‘essential+semiessential’ amino acid content of each material correlated closely with NPU, whereas scores calculated as percentages of total amino acids did not. ‘Methionine+cystine’ were calculated to be first limiting amino acids in every sample.

scholarly journals Limiting amino acids after methionine and lysine with growing turkeys fed low-protein diets

2000 ◽  
Vol 79 (9) ◽  
pp. 1290-1298 ◽  
Author(s):  
P.E. Waibel ◽  
C.W. Carlson ◽  
J.A. Brannon ◽  
S.L. Noll
Keyword(s):  
Amino Acids ◽  
Low Protein ◽  
Limiting Amino Acids ◽  
Protein Diets

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 effect of low crude protein diets supplemented with DL-methionine and L-lysine hydrochloride on male broiler performance

2005 ◽  
Vol 2005 ◽  
pp. 165-165
Author(s):  
N. Eila ◽  
H. R. Semnani
Keyword(s):  
Amino Acids ◽  
Protein Level ◽  
Crude Protein ◽  
Essential Amino Acids ◽  
Broiler Chicks ◽  
Broiler Performance ◽  
Low Protein ◽  
Limiting Amino Acids ◽  
Protein Diets ◽  
Crude Protein Level

Crude protein is an expensive nutrient in broiler diets and the supply of essential amino acids is more important than crude protein. Therefore it’s possible to reduce crude protein level by supplementing diets with methionine and lysine as limiting amino acids. The object of this study was assaying low protein diets supplemented with DL-methionine and L-lysine hydrochloride on male broiler chicks.

Significance of the ‘Protein-Sparing’ Effect of Dextrin

1958 ◽  
Vol 193 (3) ◽  
pp. 479-482 ◽  
Author(s):  
H. E. Spivey ◽  
M. C. Katayama ◽  
M. Yoshida ◽  
A. E. Harper
Keyword(s):  
Amino Acids ◽  
Corn Starch ◽  
Essential Amino Acids ◽  
Protein Utilization ◽  
Feeding Experiments ◽  
Low Protein ◽  
Protein Sparing ◽  
Ad Libitum ◽  
Sparing Effect ◽  
Protein Diets

Among the hypotheses proposed to explain the greater food intake and rate of gain of young rats fed ad libitum on low protein diets in which dextrin or corn starch has been substituted for sucrose are: a) increased synthesis of essential amino acids by intestinal microorganisms; b) improved digestion and absorption of protein owing to slower passage of diets containing dextrin through the small intestine; c) reduced destruction of amino acids in the animal body owing to more prolonged absorption of glucose from dextrin. The results of nitrogen balance and feeding experiments indicate that improvement in the efficiency of protein utilization when dextrin is substituted for sucrose is too small for any of the above hypotheses to account for the apparent ‘protein-sparing’ effect of dextrin.

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.

scholarly journals Impact of second line limiting amino acids’ deficiency in broilers fed low protein diets with rapeseed meal and de-oiled rice bran

2015 ◽  
Vol 8 (3) ◽  
pp. 350-357 ◽  
Author(s):  
C. Basavanta Kumar ◽  
R. G. Gloridoss ◽  
K. Chandrapal Singh ◽  
T. M. Prabhu ◽  
Siddaramanna ◽  
...  
Keyword(s):  
Amino Acids ◽  
Rice Bran ◽  
Rapeseed Meal ◽  
Second Line ◽  
Low Protein ◽  
Limiting Amino Acids ◽  
Protein Diets

scholarly journals Identification of limiting amino acids in methionine- and lysine-supplemented low-protein diets for turkeys

2000 ◽  
Vol 79 (9) ◽  
pp. 1299-1305 ◽  
Author(s):  
P.E. Waibel ◽  
C.W. Carlson ◽  
J.A. Brannon ◽  
S.L. Noll
Keyword(s):  
Amino Acids ◽  
Low Protein ◽  
Limiting Amino Acids ◽  
Protein Diets
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