Purpose
Because of the increasing importance of safety studies using juvenile animals, background data has been accumulated by various research institutes in the pediatric drug development. Therefore, we investigated the developmental changes in hematological and biochemical values in juvenile beagles less than 4 months old.
Materials and Methods
TOYO beagle's puppies were examined by drawing blood from the external jugular vein at 2, 4, 6, 8, 12 and 16 weeks of age. The mean ± SD for each items at each age were calculated to test for differences between the sexes. In addition, the results were compared with those of 12 months old.
Result
In hematological tests at juvenile, RBC, HGB, and HCT increased from low values, while MCV, MCH, and Ret decreased from high values. WBC showed a decreasing trend with age, although there were large individual differences at juvenile. The lymphocyte ratio decreased and the pseudo eosinophil ratio increased after 8 weeks old. Blood biochemical values followed three patterns: increase (TP, ALB, CRE, NEFA, ALT, LAP), decrease (CK, GLU, Ca, IP, γ-GTP, LDH, BUN), and increase/decrease (T-CHO, HDL-CHO, PL, F-CHO, ALP). The other items showed little variation with age. From the results of the significance test, it was judged that there was no difference between sexes. At 16 weeks, there were many test items that did not reach the values of 12 months old.
Conclusion
Variations with age were more observed in juveniles. The results of this study will provide useful basic data for blood tests in juvenile beagles.
