Antlers, the fastest growing mammal tissue on earth, are grown by male White-tailed Deer (and very occasionally females) every year and shed every year. They begin growing in the spring, usually April, and complete their growth in August or September. During this period they are covered with “velvet,” a soft skin containing blood vessels and nervous tissue that supply oxygen and nutrients to the antler. Once growth ceases, the velvet dries up and falls off or is inadvertently rubbed off. The mating season of White-tailed Deer, or rut, during which time their antlers are instrumental in establishing hierarchy and securing a mate, peaks in mid-November. Once mating is over, the disadvantages of antlers (cumbersome shape for traveling through woods, and the energy required to carry them) promote the shedding of these bony structures. Specialized cells (osteoclasts) destroy the bone tissue between the antlers and the skull and antlers are shed sometime between the end of December and the beginning of February.
Most sources state that antlers just fall off or that the buck knocks them off by striking them against a tree. My personal observation of a buck in captivity clarified the way antlers are dropped, at least in this one instance. The buck put his head down, quickly jerked it up and to one side, and the antler went flying.
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