Journal of Nutrition Animal Diets/Enrichment Products...

Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
QUICK SEARCH:   [advanced]


     

Journal of Nutrition Vol. 93 No. 4 December 1967, pp. 579-583
Copyright
This Article
Right arrow Full Text (PDF)
Right arrow Purchase Article
Right arrow View Shopping Cart
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Tagle, M. A.
Right arrow Articles by Donoso, G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Tagle, M. A.
Right arrow Articles by Donoso, G.

Effect of Protein Level on Utilization of Casein and Gluten by Weanling Rats1

María Angélica Tagle and Gonzalo Donoso

Laboratory of Nutrition, School of Public Health and Chair of Biochemistry, School of Agriculture, University of Chile, Santiago de Chile

The effect of protein level on utilization of casein and gluten by weanling rats was studied over a wide range of concentrations, from 5.1 to 59.4 protein calories per cent total calories (P%) for casein, and from 6.6 to 58.5 for gluten. The decrease in net protein utilization (NPU) with the increase in protein concentration follows a semilogarithmic curve; NPU casein equals ---56.54 log P + 121.92 and NPU gluten equals -24.35 log P+ 57.77. An equation which permits the prediction of NPU from score and protein concentration is proposed. Protein values as net dietary protein calories % (NDpCals %), calculated using predicted figures for NPU agree well with experimental values. The relationship between protein intake, as net dietary protein calories per kg0.73 (NDpCals/kg0.73) and weight gain could also permit the calculation of weight increments from predicted protein values.

1 The abbreviations used are: P, protein-to-calorie ratio; P %, a ratio of protein calories to per cent total calories; experimental NPU, net protein utilization determined experimentally (4); predicted NPU, calculated according to the formula we propose; S, protein score derived from amino acid data (5); NDpCals %, (net dietary protein calories %), percentage of the total calories of the diet supplied as wholly utilizable protein; experimental NDpCals %, (experimental NPU x P) x 100; predicted NDpCals %, (predicted NPU x P)/100; calorie intake, diet consumed in kilocalories; NDpCals intake, (calorie intake x NDpCals %)/100.

Manuscript received 25 May 1967.




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]