Abstract:As the first step to get historical background data for physiological examinations in juvenile dogs, hematology and blood chemistry data obtained from juvenile beagle dogs (less than 3 months of age) used in the control group of toxicity studies conducted in our laboratory were summarized and compared with those obtained from adult beagle dogs (6 months of age). In the hematological examination, growth of beagle dogs was shown to be associated with increases in erythrocyte parameters and with decreases in reticulocyte and leukocyte counts. In the blood chemical examination, growth of beagle dogs was shown to be associated with increases in aspartate aminotransferase, alanine aminotransferase, and creatinine and with decreases in creatine phosphokinase, glucose, total cholesterol, and calcium. The differential leukocyte ratio showed no age relation, but the actual count showed a tendency toward decrease. Alkaline phosphatase showed a tendency to increase from 0 months of age to 3 months of age, but it decreased at 6 months of age. The present results were roughly similar to those previously reported.

-In order to prepare background data for toxicity studies, serum alkaline phosphatase activity in a total of 5,242 male and female beagle dogs was surveyed for the sequence of changes in activity through aging. About 95% of the beagle dogs surveyed were 5 to 12 months of age, corresponding with the age usually employed in toxicity studies. Serum alkaline phosphatase (ALP) activity, about 460 IU/l at 5 months of age, steadily decreased and reached a level about one third of that (about 160 IU/l) at -spective of sex and breeding colony. The present results are useful information in the evaluation of blood chemistry data in toxicity studies.