Evolution of blood serum mineral composition during antler growth and rut as consequence of Cu supplementation in captive red deer and its effects in mature antler composition

Abstract

In the present study we assessed the effects of Cu supplementation and antler growth stage on mineral composition of serum and hard antler in red deer fed a balanced diet. Correlations between minerals were analysed for serum, for antlers, and between serum versus mature antler. Blood samples were drawn at Days –36, 54, 132 and 197 of the start of antler growth (SAG). Hard antlers were cut at Day 165 from SAG. The Cu supplemented group (n = 9) was injected with 0.83 mg Cu/kg of bodyweight, whereas the control group (n = 9) was injected with a physiological saline solution, both every 42 days between Days –36 (Cu supplied after blood sampling) and 132 from SAG. Supplementation with Cu increased (P < 0.05) the contents of P and Cu in serum but did not affect the antler mineral profile. Serum contents of Mg, Na, S, B and Cu increased during the antler growth, whereas contents of K, Al and Fe decreased in the same period (P < 0.001). At Day 54 from SAG in Cu group, serum P content correlated negatively with antler Ca content whereas Zn of serum and antler correlated positively (P < 0.05). The maximum number of correlations between the mineral profile of serum and hard antler was achieved at Day 132 from SAG (3.3, 4.7 and 12.9% for Days –36, 54 and 132, respectively). In conclusion, the analysis of specific minerals in serum could be used to detect in advance some mineral deficiencies in the antler.