Nutrient reserves of breeding Ring-necked Ducks (Aythya collaris)

1990 ◽  
Vol 68 (12) ◽  
pp. 2524-2530 ◽  
Author(s):  
Ray T. Alisauskas ◽  
Robert T. Eberhardt ◽  
C. Davison Ankney
Keyword(s):  
Dietary Protein ◽  
Lipid Production ◽  
Carcass Composition ◽  
Follicle Growth ◽  
Body Lipid ◽  
Body Protein ◽  
Protein Requirements ◽  
Daily Rate ◽  
Lipid Stores ◽  
Nutrient Reserves

We studied carcass composition of Ring-necked Ducks, Aythya collaris, collected on breeding areas in Beltrami County, Minnesota. Females collected before they had commenced rapid growth of ovarian follicles apparently stored body lipid and body protein. For every gram of egg lipid produced, somatic lipid stores declined by 0.48 g at all stages of rapid follicle growth, irrespective of the daily rate of egg lipid production. A decline in body protein coincided with increased daily requirements for clutch proteins. However, females increased their protein reserves from mid to late rapid follicle growth, resulting in no difference between reserves of females starting and terminating rapid follicle growth. We suggest that observed patterns of lipid storage by Ring-necked Ducks, and possibly by other species of temperate-nesting ducks, have evolved to allow supply of clutch lipids at a rate in line with the ease with which we suspect that breeding hens are able to procure dietary protein; the high daily protein requirements to meet protein demands of clutch formation are possible to meet because ducks typically nest near wetlands in which there is a large seasonal flush of invertebrates.

Dietary protein requirements and body protein metabolism in endurance-trained men

1989 ◽  
Vol 66 (6) ◽  
pp. 2850-2856 ◽  
Author(s):  
C. N. Meredith ◽  
M. J. Zackin ◽  
W. R. Frontera ◽  
W. J. Evans
Keyword(s):  
Dietary Protein ◽  
Protein Turnover ◽  
Protein Intake ◽  
Whole Body ◽  
Middle Aged ◽  
Body Protein ◽  
Protein Requirements ◽  
High Quality Protein ◽  
Effect Of Age ◽  
Lower Physical Activity

The effects of regular submaximal exercise on dietary protein requirements, whole body protein turnover, and urinary 3-methylhistidine were determined in six young (26.8 +/- 1.2 yr) and six middle-aged (52.0 +/- 1.9 yr) endurance-trained men. They consumed 0.6, 0.9, or 1.2 g.kg-1.day-1 of high-quality protein over three separate 10-day periods, while maintaining training and constant body weight. Nitrogen measurements in diet, urine, and stool and estimated sweat and miscellaneous nitrogen losses showed that they were all in negative nitrogen balance at a protein intake of 0.6 g.kg-1.day-1. The estimated protein requirement was 0.94 +/- 0.05 g.kg-1.day-1 for the 12 men, with no effect of age. Whole body protein turnover, using [15N]glycine as a tracer, and 3-methylhistidine excretion were not different in the two groups, despite lower physical activity of the middle-aged men. Protein intake affected whole body protein flux and synthesis but not 3-methylhistidine excretion. These data show that habitual endurance exercise was associated with dietary protein needs greater than the current Recommended Dietary Allowance of 0.8 g.kg-1.day-1. However, whole body protein turnover and 3-methylhistidine excretion were not different from values reported for sedentary men.

scholarly journals Effect of dietary protein on energy metabolism including protein synthesis in the spiny lobster Sagmariasus verreauxi

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuangyao Wang ◽  
Chris G. Carter ◽  
Quinn P. Fitzgibbon ◽  
Basseer M. Codabaccus ◽  
Gregory G. Smith
Keyword(s):  
Protein Synthesis ◽  
Energy Metabolism ◽  
Dietary Protein ◽  
Spiny Lobster ◽  
Ammonia Excretion ◽  
Metabolic Energy ◽  
Whole Body ◽  
Body Protein ◽  
Energy Substrate ◽  
Sagmariasus Verreauxi

AbstractThis is the first study in an aquatic ectotherm to combine a stoichiometric bioenergetic approach with an endpoint stochastic model to explore dietary macronutrient content. The combination of measuring respiratory gas (O2 and CO2) exchange, nitrogenous (ammonia and urea) excretion, specific dynamic action (SDA), metabolic energy substrate use, and whole-body protein synthesis in spiny lobster, Sagmariasus verreauxi, was examined in relation to dietary protein. Three isoenergetic feeds were formulated with varying crude protein: 40%, 50% and 60%, corresponding to CP40, CP50 and CP60 treatments, respectively. Total CO2 and ammonia excretion, SDA magnitude and coefficient, and protein synthesis in the CP60 treatment were higher compared to the CP40 treatment. These differences demonstrate dietary protein influences post-prandial energy metabolism. Metabolic use of each major energy substrate varied at different post-prandial times, indicating suitable amounts of high-quality protein with major non-protein energy-yielding nutrients, lipid and carbohydrate, are critical for lobsters. The average contribution of protein oxidation was lowest in the CP50 treatment, suggesting mechanisms underlying the most efficient retention of dietary protein and suitable dietary inclusion. This study advances understanding of how deficient and surplus dietary protein affects energy metabolism and provides approaches for fine-scale feed evaluation to support sustainable aquaculture.

Effect of dietary protein on bed-rest-related changes in whole-body-protein synthesis

1990 ◽  
Vol 52 (3) ◽  
pp. 509-514 ◽  
Author(s):  
C A Stuart ◽  
R E Shangraw ◽  
E J Peters ◽  
R R Wolfe
Keyword(s):  
Protein Synthesis ◽  
Dietary Protein ◽  
Bed Rest ◽  
Whole Body ◽  
Body Protein

scholarly journals Comprehensive assessment of post-prandial protein handling by the application of intrinsically labelled protein in vivo in human subjects

2021 ◽  
pp. 1-9
Author(s):  
Jorn Trommelen ◽  
Andrew M. Holwerda ◽  
Philippe J. M. Pinckaers ◽  
Luc J. C. van Loon
Keyword(s):  
Protein Synthesis ◽  
Amino Acid ◽  
Stable Isotope ◽  
Dietary Protein ◽  
Protein Metabolism ◽  
Muscle Protein ◽  
Human Subjects ◽  
Whole Body ◽  
Body Protein

All human tissues are in a constant state of remodelling, regulated by the balance between tissue protein synthesis and breakdown rates. It has been well-established that protein ingestion stimulates skeletal muscle and whole-body protein synthesis. Stable isotope-labelled amino acid methodologies are commonly applied to assess the various aspects of protein metabolism in vivo in human subjects. However, to achieve a more comprehensive assessment of post-prandial protein handling in vivo in human subjects, intravenous stable isotope-labelled amino acid infusions can be combined with the ingestion of intrinsically labelled protein and the collection of blood and muscle tissue samples. The combined application of ingesting intrinsically labelled protein with continuous intravenous stable isotope-labelled amino acid infusion allows the simultaneous assessment of protein digestion and amino acid absorption kinetics (e.g. release of dietary protein-derived amino acids into the circulation), whole-body protein metabolism (whole-body protein synthesis, breakdown and oxidation rates and net protein balance) and skeletal muscle metabolism (muscle protein fractional synthesis rates and dietary protein-derived amino acid incorporation into muscle protein). The purpose of this review is to provide an overview of the various aspects of post-prandial protein handling and metabolism with a focus on insights obtained from studies that have applied intrinsically labelled protein under a variety of conditions in different populations.

scholarly journals Presleep dietary protein-derived amino acids are incorporated in myofibrillar protein during postexercise overnight recovery

2018 ◽  
Vol 314 (5) ◽  
pp. E457-E467 ◽  
Author(s):  
Jorn Trommelen ◽  
Imre W. K. Kouw ◽  
Andrew M. Holwerda ◽  
Tim Snijders ◽  
Shona L. Halson ◽  
...  
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Dietary Protein ◽  
Myofibrillar Protein ◽  
Whole Body ◽  
Body Protein ◽  
Protein Ingestion ◽  
Casein Protein ◽  
The Impact ◽  
Myofibrillar Protein Synthesis

The purpose of this study was to determine the impact of ingesting 30 g casein protein with and without 2 g free leucine before sleep on myofibrillar protein synthesis rates during postexercise overnight recovery. Thirty-six healthy young men performed a single bout of resistance-type exercise in the evening (1945) after a full day of dietary standardization. Thirty minutes before sleep (2330), subjects ingested 30 g intrinsically l-[1-13C]phenylalanine-labeled protein with (PRO+leu, n = 12) or without (PRO, n = 12) 2 g free leucine, or a noncaloric placebo (PLA, n = 12). Continuous intravenous l-[ ring-2H5]phenylalanine, l-[1-13C]leucine, and l-[ ring-2H2]tyrosine infusions were applied. Blood and muscle tissue samples were collected to assess whole body protein net balance, myofibrillar protein synthesis rates, and overnight incorporation of dietary protein-derived amino acids into myofibrillar protein. Protein ingestion before sleep improved overnight whole body protein net balance ( P < 0.001). Myofibrillar protein synthesis rates did not differ significantly between treatments as assessed by l-[ ring-2H5]phenylalanine (0.057 ± 0.002, 0.055 ± 0.002, and 0.055 ± 0.004%/h for PLA, PRO, and PRO+leu, respectively; means ± SE; P = 0.850) or l-[1-13C]leucine (0.080 ± 0.004, 0.073 ± 0.004, and 0.083 ± 0.006%/h, respectively; P = 0.328). Myofibrillar l-[1-13C]phenylalanine enrichments increased following protein ingestion but did not differ between the PRO and PRO+leu treatments. In conclusion, protein ingestion before sleep improves whole body protein net balance and provides amino acids that are incorporated into myofibrillar protein during sleep. However, the ingestion of 30 g casein protein with or without additional free leucine before sleep does not increase muscle protein synthesis rates during postexercise overnight recovery.

scholarly journals Relationships of retained energy and retained protein that influence the determination of cattle requirements of energy and protein using the California Net Energy System

2018 ◽  
Vol 3 (3) ◽  
pp. 1029-1039 ◽  
Author(s):  
Luis O Tedeschi
Keyword(s):  
Body Fat ◽  
Energy System ◽  
The Body ◽  
Metabolizable Energy ◽  
Net Energy ◽  
Body Protein ◽  
Protein Requirements ◽  
Growing Cattle ◽  
Lower Correlation

Abstract Interrelationships between retained energy (RE) and retained protein (RP) that are essential in determining the efficiency of use of feeds and the assessment of energy and protein requirements of growing cattle were analyzed. Two concerns were identified. The first concern was the conundrum of a satisfactory correlation between observed and predicted RE (r = 0.93) or between observed and predicted RP when using predicted RE to estimate RP (r = 0.939), but a much lower correlation between observed and predicted RP when using observed RE to estimate RP (r = 0.679). The higher correlation when using predicted vs. observed RE is a concern because it indicates an interdependency between predicted RP and predicted RE that is needed to predict RP with a higher precision. These internal offsetting errors create an apparent overall adequacy of nutrition modeling that is elusive, thus potentially destabilizing the predictability of nutrition models when submodels are changed independently. In part, the unsatisfactory prediction of RP from observed RE might be related to the fact that body fat has a caloric value that is 1.65 times greater than body protein and the body deposition of fat increases exponentially as an animal matures, whereas body deposition of protein tends to plateau. Thus, body fat is more influential than body protein in determining RE, and inaccuracies in measuring body protein will be reflected in the RP comparison but suppressed in the RE calculation. The second concern is related to the disconnection when predicting partial efficiency of use of metabolizable energy for growth (kG) using the proportion of RE deposited as protein—carcass approach—vs. using the concentration of metabolizable energy of the diet—diet approach. The culprit of this disconnection might be related to how energy losses that are associated with supporting energy-expending processes (HiEv) are allocated between these approaches. When computing kG, the diet approach likely assigns the HiEv to the RE pool, whereas the carcass approach ignores the HiEV, assigning it to the overall heat production that is used to support the tissue metabolism. Opportunities exist for improving the California Net Energy System regarding the relationships of RE and RP in computing the requirements for energy and protein by growing cattle, but procedural changes might be needed such as increased accuracy in the determination of body composition and better partitioning of energy.

Reevaluation of the Dietary Protein Requirements and Optimum Dietary Protein to Energy Ratios in Japanese Eel, Anguilla japonica

2007 ◽  
Vol 38 (3) ◽  
pp. 418-426 ◽  
Author(s):  
Okorie E. Okorie ◽  
Young-Chul Kim ◽  
Seunghyung Lee ◽  
Jun-Young Bae ◽  
Jin H. Yoo ◽  
...  
Keyword(s):  
Dietary Protein ◽  
Anguilla Japonica ◽  
Japanese Eel ◽  
Protein Requirements ◽  
Energy Ratios
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