Correlation between antler and long bone relative bone mass and circulating androgens in white-tailed deer (Odocoileus virginianus).

The relationship between serum androgen concentrations and relative density changes in the antlers and long bones of male deer was determined. Four male white-tailed deer were sampled 2 times a week during the antler-growing period. Serum androgen values were determined by radioimmunoassay, and relative bone mass (RBM) coefficients were determined by radiograph densitometry. As circulating androgen concentrations increased over the antler-growing period, the RBM coefficients of the antler increased from a mean of 18.5 (+/- 1.96 SD) to a mean of 57.7 (+/- 2.74) at 2 weeks after "rubout." Concurrently, the RBM coefficients of the metacarpus decreased from a mean of 52.0 (+/- 1.92) to a mean of 46.4 (+/- 1.86). There were positive correlation between increasing androgen concentrations and increasing antler RBM and negative correlation between androgens and decreasing metacarpus RBM. Antler RBM coefficients continued to increase after rubout, but metacarpus RBM did not change after rubout. Two castrated deer were injected subcutaneously with 1 g of testosterone and sampled every other day. Similar but smaller changes occurred in RBM values of the metacarpus and developing antler.