The Growth of Deer Antlers

Deer antlers are bones that grow anew each year. They can weigh from 3 to 9 lbs. Antler growth begins in the spring and ends in the fall, when the antler tissue stops growing and the bone dies. At the end of the fall, the antlers fall off. These discarded antlers are called sheds.

  1. Pedicles

    • Pedicles are permanent skin-covered knobs on the heads of both male and female deer. It is from the pedicles that the antlers grow and break off. Antler growth is controlled by hormones that are regulated based on the amount of sunlight in the day. While only male deer typically grow antlers, females with hormone imbalances can grow them too, according to the Wisconsin Department of Natural Resources.

    Features

    • Antler bone is the fastest growing tissue in any mammal. They can grow as fast as 1 inch per day. Antlers are not horns. The difference is that horns are not shed, are covered in a tough coat of keratin (not pure bone) and have age rings, like the rings of a tree, according to the Isaak Walton League of America.

    Early Growth

    • In the early stages of growth, antlers are covered in soft velvet that provides nutrients for the growing antlers over the course of several months. They are sensitive during these early growth stages, and have a rich blood supply. If an antler is broken or damaged during this stage, it can remain malformed for the rest of the year.

    Mid-Growth

    • During the early summer, antlers are spongy but gradually harden as the season progresses. With the gradual hardening of the antlers comes a gradual increase in testosterone in response to the longer summer days. During this mid-growth period, bucks are typically calm and travel in bachelor groups, avoiding does, according to Texas Parks and Wildlife.

    End Growth

    • When antlers have reached their full size, bucks begin the process of rubbing off the velvet on tree trunks and brush, exposing the hard bone beneath in preparation for rutting. Rutting, or mating, involves competition between bucks for does, and fully formed horns are used in battle. As the buck rubs off the velvet, he strengthens his neck muscles, atrophied from the long winter. Increased testosterone stimulates muscle growth as well, according to the Wisconsin Department of Natural Resources. At the end of the fall, after rutting, the antlers will fall off and the buck will start the process all over again.