Growth and Maintenance of Dogs Fed Amino Acids as the Source of Dietary Nitrogen
One Figure
R. H. Silber,
E. E. Howe,
C. C. Porter and
C. W. Mushett
Merck Institute for Therapeutic Research and the Research Laboratories of Merck and Co., Inc., Rahway, New Jersey
1. Two adult dogs were fed a peptide-free mixture of amino acidsas the sole source of nitrogen, orally for 40 days and intravenouslyfor an additional 24 days. Body weights, serum protein concentrations,and nitrogen balace were maintained. No biochemical, hematologicalor pathological evidence of toxicity or deficiency was observed.
2. Two pups were fed for 12 weeks a diet containing a peptide-freemixture of amino acids as the sole source of nitrogen. Theiraverage gain in weight was 0.40 kg per week. Pair-fed animalsreceiving a casein diet gained 0.43 kg per week. There was noindication that the amino acid mixture produced toxic effects,other than an initial transient nausea.
3. Peptides do notappear to be essential for the growth ormaintenance of dogs.