The pedicels which begin growing at a couple months of age in buck fawns provide the base from which the antler will grow. They are not antlers. Infantile antlers or actual hardened antlers on a buck fawn have not been documented in Virginia but have been reported in other states.
Deer grow their first set of antlers when they are approximately one year of age. For example, it would be possible to surgically produce a unicorn deer or a deer with 10 antlers growing out of its skull or any other part of the body. The annual antler cycle is ultimately controlled by day length or photoperiod. The brain contains a kind of clock that measures the periods of light and dark and uses this information to ultimately control the secretion of the reproductive hormone testosterone in males.
Testosterone controls the antler cycle. In tests, bucks kept in constant 12 hours of light and dark were unable to shed their antlers and grow new ones, and bucks kept in constant light grew and lost three sets of antlers in two years. Growth of antlers typically begins in April in response to increasing day length. Antler growth begins by a bud forming on the pedicel. Within a month the first tine or brow tine will have begun to form or split off. Approximately a month later, the second tine G2 will have begun to form.
In just four months, the antlers are fully developed. During the summer months of antler growth, bucks live in reclusive bachelor groups and restrict their movements. What is first built is the structure or a frame or matrix.
Think of pouring concrete; you must first build a form. That is what deer do. During the early summer, deer antlers are soft to the touch or spongy. By late summer, as day length decreases, testosterone levels begin to increase, the form is filled, and the antler begins to harden. Finally the blood vessels within the antler itself are filled and lose their ability to nourish the velvet, and it dries up and falls off.
The velvet is typically totally removed in a day, and some of it may be eaten by the buck. In Virginia, most deer are in hard antler by September 15th. Contrary to popular belief, deer do not rub their antlers on trees just to remove the velvet. In any given year, an individual buck may make hundreds of rubs, Hard antlers remain on the deer through the peak of breeding mid November in Virginia until late fall or early winter.
In response to continuing shortening of daylight and decreasing testosterone levels after the rut, an abscission zone forms at the junction of the pedicel and antler.
An erosion of the bone takes place at this seam and eventually the antler falls off, leaving a bloody depression which quickly scabs over. Caribou also known as reindeer use their antlers to scrape away snow and soil to find food, as well as to defend themselves. Both male and female caribou have antlers, making them the only deer species in which females have antlers! Large antlers have lots of surface area to allow for body temperature regulation while they are growing, and their impressive design can both show status and attract mates.
Moose and their massive antlers are native to nearly all northern forest zones Europe, North America, Siberia, Baltic States, and parts of Asia. These antlers can grow to be really big—moose antlers can have a six-foot spread! Their impressive size can attract mates, as well as warn other bulls males to stay away. Their extremely long legs are helpful in such snowy regions, but these environments are changing with global warming. Elk were once seen all over North America, but now these animals are mainly found in heavily wooded areas of the American West.
Developing antlers have blood vessels underneath a velvety skin, which can help to regulate an animal's body temperature. Large antlers might also attract mates and intimidate rivals because healthier elk will have larger sets. Bull male elk use their antlers to fight each other for mates and territory.
White-tailed deer are by far the most widespread ungulate hoofed animal in the Americas; you can spot them from Canada all the way down to parts of northern South America. Females retain their antlers until spring, because access to food is critical during their winter pregnancy. Some scientists therefore argue that Rudolph, who is universally depicted in late December with intact antlers, is female.
In fact, most of the reindeer used to pull sleds are castrated males — they are easier to handle, and have antler cycles similar to those of the females. Not all females have antlers, however, because growing them costs a lot of energy. In habitats where food is scarce or of poor quality, antlerless females dominate.
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