Libraries at University of Nebraska-Lincoln

 

Document Type

Thesis

Date of this Version

5-1969

Citation

Thesis (M.S.)—University of Nebraska—Lincoln, 1969. Department of Foods and Nutrition.

Comments

Copyright 1969, the author. Used by permission.

Abstract

The present study deals with the nutritional protein quality of high protein wheat for growing rats and baby pigs. The potential improvement of the cereal quality by essential and non-essential supplementation was investigated.

Wheat, the main source of protein, was fed alone or supplemented with the purified essential amino acid lysine, methionine and/or threonine. Clycine was the source of non-essential nitrogen. Criteria used for evaluating protein quality were average daily weight gain, average daily food intake and gain per unit of food intake. In the experiment with baby pigs only one variety of wheat, high protein wheat (HPW) was used. The level of protein was the same for all the diets. The diets were supplemented with essential and non-essential amino acids as follows: (1) high protein wheat (HPW), (2) HPW + lysine, (3) HPW + lysine + methionine, (4) HPW + lysine + threonine, (5) HPW + lysine, methionine and threonine and, (6) HPW + ½ (essential amino acids used in diet 5) + glycine. Results showed no differences in feed consumption among the treatments. Higher weight gains were obtained with the supplemented diets (P < .01) than with the unsupplemented one. Among the supplemented diets a decrease in growth (P < .05) was observed in diets, in which one-half the amount of essential amino acid of diet 5 was used. According to the results of this experiment HPW when fed alone is not adequate for supporting growth in baby pigs. Lysine appeared to be the most limiting amino acid since growth response induced by the addition of lysine was not improved significantly by the addition of methionine and/or threonine.

In the second study two varieties of wheat, HPW and regular protein wheat (RPW), were used as main sources of protein for feeding growing rats. The wheat was fed alone or supplemented with essential and/or non-essential nitrogen. The diets were: (1) RPW (11.2% protein), (2) HPW (16.2% protein), (3) HPW diluted with sucrose, (4) RPW + glycine (isonitrogenous to diet 2), (5) HPW diluted with sucrose to 14% protein, (6) HPW + glycine to 28% protein, (7) HPW + EAA (lysine, methionine, threonine) + glycine and, (8) RPW + ½ EAA (used in diet 7) + glycine. Diets 7 and 8 were isonitrogenous with diet 6. The greater gain in weight achieved by rats fed the unsupplemented HPW diets suggested that this wheat at 16.2% protein was a fairly satisfactory source of protein for growing rats. High levels of glycine used as a source of supplementary nitrogen inhibited growth response of rats. RPW contained insufficient quantities of essential amino acids for support of satisfactory growth in rats and was not improved by the addition of non-essential nitrogen alone.

Advisor: Hazel M. Fox

Share

COinS