Importance of growth during lactation on body size and antler development in the Iberian red deer (Cervus elaphus hispanicus)

Lactation appears to be an influential factor for the adult size of male deer and thus, it could also influence the size of the antlers. This study examined the effects of lactation on body weight and antler size of male Iberian red deer up to 2 years of age. Several body and antler measurements were related to the production and composition of milk and calf growth during lactation. Results showed that calf weight gains during lactation affected body weight and other parameters of calves at 1 year of age, and there is evidence that, even in ad libitum food conditions during post weaning period, some lactation effects could extend up to 2 years of age. High percentage of milk protein resulted in increased antler weight or length. Results also suggested that body growth during this early stage might affect antler size positively through growth precocity. Thus, males that reached a higher weight at weaning also developed antlers earlier. Antlers that developed earlier were also heavier and had a greater base perimeter.