Effect on Body Growth of Small Doses of Testosterone Propionate Administered at Different Seasons

Summary and Conclusions

Testosterone propionate (Perandren) was subcutaneously injected through the 4 seasons into 4 respective groups of male albino rats in daily doses of 50 γ from 26 to 80 days. Final body weight in the treated animals was observed to be 188.2±2.3 g; of the controls 172.4±2.4 g. The difference of 15.8±3.3 g in favor of the treated animals (S.R.= 4.8) was “probably significant.” Final body length of the treated group (196±1.2 mm) was 4.8±1.4 mm longer than that of controls (191.2±1.1 mm). This was also “probably significant” (S.R.=3.4). Because of initial weight differences among the controls for the different seasons and because of a significant difference between the initial body weights of one treated group and their respective controls, comparisons were also made of “weight-gains” during the periods of observation. It was found that the treated animals gained 17.8±3.2 g more than their controls. This difference in weight-gain was considered to be statistically “probably significant” (S.R.=5.5). Although animals whose treatment began in April failed to show abnormally rapid growth those groups receiving injections during the Fall, Winter and Summer did become significantly larger than their respective controls.

It is therefore concluded that while animals generally respond to appropriately small doses of testosterone propionate with increased body weight and length, seasonal variation is a potent factor in the results obtained.