Growth rate slows dramatically during late summer while mineralization of the antler is completed. Restriction of blood supply around the autumn equinox causes the velvet's death; when dry enough, velvet is removed in as little as 24 hours by thrashing on vegetation. Well after the breeding season, cells called osteoclasts de-mineralize the bone along an abscission line where the pedicle meets the antler. This weakened attachment combined with the weight of the antler causes it to drop off or be cast.
Although described as an abscission "line," the surface of the detached antler base is rough in texture.
The resulting surface may be either flush with or extend beyond the burr or coronet. Brain abscesses, resulting from secondary infection following injury to the frontal bone or pedicle, may result in a jagged abscission line projecting deep into the pedicle and frontal bone. Once the antler is cast, the top of the pedicle can be considered an open wound.
This area reacts like any wound, bleeding for a short period and developing a scab-like covering called a "wound epithelium" within weeks. Antler growth begins shortly after completion of the wound epithelium in white-tailed deer and most members of the deer family; in contrast, moose antlers do not begin growth until two — three months after antler casting.
The covering of the growing antler takes on the appearance of shiny velvet because sparse hairs grow straight out and are coated with oily secretions from the hair follicle. Beneath the velvet epidermis and dermis of the growing antler is a thick, fibrous protective membrane, called perichondrium when it covers the cartilagenous growth stage and periosteum when it covers the boney stage of the growing antler.
Beneath the velvet and perichondrium lies the mesenchyme growth zone, an area of rapid cell generation and growth. In the chondroprogenitor region these young cells begin to differentiate into chondrocytes and to form the columnar structure characteristic of cartilage and bone. The enlarged and columnar chondrocytes then begin the process of mineralization.
Once mineralized, chondroclasts resorb the cartilage, and bone is laid down on the remaining "scaffold" by osteoblasts. For more details on this process see the review by Price et al. There are two types of bone within an antler, spongy bone and compact cortical bone. Of course, genetics are difficult to manage if you want to grow bigger deer antlers in your deer population.
While you may not know each individual deer's parents, you can look at the deer in your area since they are all most likely related. You should watch for trends in antler size and shape in your area during the spring and summer to prepare for hunting season in the fall. The buck reaches antler maturity at six years.
Over its lifetime, the deer will develop and shed antlers, with new, uniquely-shaped antlers appearing each time. Generally, antlers grow in about days. This timeline of deer antler growth by year demonstrates what antlers will look like with age after the deer grows and sheds its antlers throughout the year. While their antlers come in all shapes and sizes, most of their antlers look like thin beams sticking out by their ears. The deer that will have the strongest and largest antlers later in life are those that have multiple tines at a young age.
By this point, a healthy buck should have antlers as wide as its ears. They may also start showing signs of how many deer tines they will have when they fully mature. Most bucks have reached more than half of their optimal antler growth by three years old.
At this age, its neck should be full and its chest should be deep. The spread of the antlers should grow past the width of the ears with an adequate mass.
At four years old, the buck has developed into a strong, healthy deer. It is skinnier than it will be at full maturity. Most bucks reach more than three-quarters of their optimal antler growth at age four.
Generally, bucks' antlers fully mature between five and seven years old. During this time, they have also reached their optimal body mass to have a full, strong appearance. The fullness and complexity of their antlers will depend on their access to nutrition and their genetic makeup. Since most free-range deer are hunted during their prime age of five to seven, you will find few deer older than eight years old. Until this age, deer antlers get bigger each year. As deer age, the shape and size of their antlers will decrease and their body mass will shrink.
A deer of this age will have weathered antlers to show their fights with other deer and their journey through life. Whitetail deer begin to grow their antlers in the spring, and you'll start to see deer losing antlers in the winter.
Here is the general timeline of the whitetail deer antler growth process by month. Deer begin to grow antlers between late March and early April. During this time, two stumps of bone pop out from the deer's pedicles, wrapped in a thin layer of velvet skin. The velvet contains the oxygen and nutrients needed for the antlers to grow into healthy, mature antlers.
When the antlers of the whitetail deer are in velvet, deer try to keep their antlers from injury. Any injuries brought on by weather, knocking into objects or other deer could result in abnormalities in their antlers. Since deer use nutrients from their entire body — such as the bones in their legs — they need to have proper nutrition from a young age. April In the middle of spring, May is when more nutritious foods are available to bucks.
During this time, whitetails prefer food and forage that is high in protein and other essential nutrients. With time to fully recover from the winter, the whitetail deer's body can now fully focus on antler growth. At the end of May, deer should start to show a second point on their deer rack. The antler beams should also be about half of what their length will be at full maturity.
May During the summer, after a healthy season of rainfall, lush, nutritious food will be available for deer to continue their growth process. With more daylight available in June, deer produce the hormones needed to accelerate the antler growth process. By the end of June, a deer will have grown nearly all the primary points on its antler racks. At the beginning of this mid-summer month, the buck's antlers should be very bulbous.
Throughout the month, the beams and points of the antler will grow. By the middle of July, the buck should have massive mature antlers. Adequate rainfall in the spring and summer will make more nutrition-rich foods available to deer to promote health antler growth. Antler growth could be hindered by a drought and a lack of nutritious foods for the deer. By the end of July, most bucks' antlers have fully formed, and they can begin the hardening process.
Most bucks will complete their antler growth in the middle of August when the blood flow to the antlers decreases. The antlers will harden over the next 20 to 25 days. Pedicle Development. The two circular areas that grow antlers from a buck's skull are known as pedicles. Antler pedicles start developing on the frontal bones of male whitetail deer fawns during late fetal development. After birth, early stimulation from testosterone is then required for final pedicle development. When bucks reach months of age, the antlers begin to grow from the pedicle.
Deer Antler growth usually begins during the early Spring in response to changes in growth hormones from the pituitary gland which stimulates antler growth. During this time, the soft growing antler is covered with hairy skin, called "velvet". When antlers are in the velvet stage they are full of blood vessels, cartilage and nervous tissue. By early Fall, rising testosterone levels and testicular volume, harden antlers through calcification.
In this process, soft tissue is converted directly to bone by the deposit of minerals within the cartilage and blood vessels in the developing antlers. The buck will help it along by rubbing his antlers on trees, shrubs and saplings. Definition of Antlers. They range from tiny sharp spikes to amazing typical and non-typical racks.
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