COMPARATIVE EFFECT OF AMINO-ACID MIXTURES WITH OR WITHOUT ASPARAGINE AND GLUTAMINE ON GROWTH OF RATS

When proteins, peptides and amino acid mixtures are compared, some amino acid mixtures include asparagine and/or glutamine and others do not. Therefore in this experiment we studied the effect of the presence or absence of these amino acids on the growth and nutritional status of rats. Rats weighing about 65 g were divided into 4 groups and fed experimental diets for 21 days. The diets contained 11% casein (N = 1.57%, group A), 10% amino acid mixture (N = 1.57%, including asparagine and glutamine, group B), 10% amino acid mixture (N = 1.25%, excluding asparagine and glutamine, group C), or 12.5% amino acid mixture (N = 1.57%, excluding asparagine and glutamine, group D). In group D we increased amino acid concentration to 12.5% in order to make N concentration same as the diets of groups A and B. Daily food intake, body weight gain and hematologic values were measured. Most of the indicators of groups A, B and C were similar and lower than those of group D. The results suggest that amino acid mixtures excluding asparagine and glutamine have the same effect as protein and the mixture including these amino acids on growth and nutritional status of young rats but overestimates the effect when total N concentration is increased to the level of protein.