Lactation growth influences mineral composition of first antler in Iberian red deer Cervus elaphus hispanicus

Deer antlers are bony fighting structures which are unique in that they are both easily accessible for analysis and that they are grown every year; thus, they make up good models for the study of bones. Previous studies have shown that antler bone composition is related to the external quality (antler size and weight) and the mechanical quality of the antlers, and that it reflects mineral nutrition and early growth. Because one of the main nutritional factors influencing early growth is maternal milk production and composition, and because lactation plays an important role in positive-weaning growth, we set out to examine whether milk yield mid composition are correlated with the mineral composition of spike antlers of 22 yearling Iberian red deer Cervus elaphus hispanicus. Total milk protein yield was positively associated with ash, Ca and P content in antler, inversely with K content, but no relationship was found for Na, Mg, Fe or Zn. This associition was evidently exerted through an increase in calf growth during lactation, because in the model, the inclusion of calf weight gain up to week 18 (approximately the age at weaning) rendered milk production and composition non-significant. However. this correlation was not observed for the minor minerals Na, Mg, Fe and Z. Gains during lactation, but not between lactation and antler growth, influenced the composition of major minerals. Manipulating milk quality could not only affect general calf growth, but also antler quality and very likely the quality of other bones, as well as mechanical performance, which is linked to ash or Ca content.