Antler growing cycles

Each year, antlers drop off and fully regenerate in a growth cycles.  

Each antler growth cycle includes:

• initiation

• rapid growth (velvet phase)

• mineralisation

• velvet shedding

• antler casting

Various factors control the different phases

Control of antler growth

Being male secondary sexual characters, both pedicle formation and the subsequent antler growth cycle is under the control of testosterone.  Testosterone levels at the various stages of the growth cycle are shown in the following table.

The factor responsible for stimulating antler growth is insulin-like growth factor 1 ('IGF1').  The timing of the peak of IGF1 production is regulated by day length but the key factor influencing the amount of IGF1 production is nutrition.  Good nutrition is therefore required to grow big antlers to the animal's full genetic potential.  For more on the role of nutrition, see the section on quality.