Bone turnover associated with antler growth in red deer (Cervus elaphus)

Although it is known that skeletal bone depletion occurs during antler grow th in deer, it is not clear whether repletion of the skeleton takes place b efore or after completion of antler development. This study attempted to co rrelate repeated scanning electron microscopic measures of ilium and rib bo ne porosity from six approximately 2-monthly biopsy samples (using back-sca ttered imaging) and biochemical markers of bone turnover (serum hydroxyprol ine and osteocalcin concentrations) taken for 11 months with antler growth in six red deer stags. No changes were detected in ilium samples but change s in porosity of rib bones and an elevation of the biochemical markers indi cated that skeletal depletion occurred during the antler growth period. How ever, the decrease in rib bone porosity and decline in markers of bone turn over took place before completion of antler growth, indicating that a consi derable amount of skeletal repletion could have occurred whilst antlers wer e also undergoing bone accretion. This latter finding extends the current v iew of antler growth being accompanied by a form of reversible osteoporosis in the skeleton by showing that there is a period when the antlers and ske leton are both undergoing not bone formation. Anat Rec 256:14-19, 1999. (C) 1999 Wiley-Liss, Inc.