Inter-specific differences in the structure and mechanics but not the chemical composition of antlers in three deer species

Antlers are costly structures produced annually by male cervids using minerals obtained from their diet and from resorption of their skeleton. Availability and nutritive quality of food resources therefore have a great impact on the investment of males in these secondary sexual traits. We studied the structure, mineral composition and mechanical quality of antlers of the Siberian wapiti (Cervus canadensis sibiricus), Pere David's deer (Elaphurus davidianus) and Vietnamese sika deer (Cervus nippon pseudaxis), three closely-related cervid species. The three herds investigated were maintained under the same feeding and management conditions (one male per herd) throughout a 3-year study period. We showed that there was no significant inter-specific difference in antler composition of the three species under the same feeding regime. However, mechanical properties varied between the Siberian wapiti and the other two species; and structural characteristics were different among all of them. Our results show that antler composition has a similar chemical profile across species when grown under the same feeding regime whereas the internal structure and mechanical properties appear to be species dependent.