![]() ![]() Pedicle development is chemically controlled by steroids. If the pedicle is removed, antlers can no longer develop. The pedicle increases its diameter throughout the stag's life, by annual deposition of a ring of bone. The pedicle develops from the periosteum of the frontal bone and has the same structure as that bone. Instead, they emanate from the top of permanent bumps on the head called pedicles, which begin development in the foetus. For more on the role of nutrition, see the section on quality >Īntlers do not grow directly from deer skulls. Good nutrition is therefore required to grow big antlers to the animal's full genetic potential. 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. The factor responsible for stimulating antler growth is insulin-like growth factor 1 ('IGF1'). Testosterone levels at the various stages of the growth cycle are shown in the following table. Control of antler growthīeing male secondary sexual characters, both pedicle formation and the subsequent antler growth cycle is under the control of testosterone. Various factors control the different phases. Upon casting, the nerves degenerate back to the pedicle and regenerate upon antler re-generation.Įach year, antlers drop off and fully regenerate in a growth cycles. The posterior border of the pedicle is also supplied by sensory branches of the first cervical nerves. Innervation to the antler is by the trigeminal nerve by way of supraorbital temporal branches, which are close to the lateral and medial coronal arteries. One large vein accompanies the lateral arterial arteries and one smaller vein accompanies the medial arteries, both of which eventually join the superficial temporal vein. Blood supply diminishes as calcification progresses. Deoxygenated venal blood is returned through the antler core. Below the pedicle, the superficial temporal arteries give rise to large lateral coronal arteries and smaller medial coronal artiers which ascend the antler in the vascular layer of the velvet to supply blood to the velvet and bone. Blood supplyīlood supply to the pedicles is from internal vascular supply to the frontal bones, from branches of the superficial temporal arteries. It is able to absorb a considerable amount of energy under impact before breaking. Its resistance to impact is greater than ivory. Organic matter contributes 39% to antler weight and water content is 8%.Īntler has greater tensile strength but less elasticity than the human tibia. Mature antler is similar to compact skeletal bone in composition, being 25% calcium and 19% phosphorus. The lower (non-growing) regions of the growing antler are composed of further types of cells again (chondroblasts and osteoblasts), as shown in the following diagram. The growing tip of the antler is composed of various types of cells (mesenchymal, pre-chondroblasts and chondroblasts) and is covered by a layer of tissue (comprising epidermis and dermis). ![]()
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