horn and antler SDL

Question 1

describe the structure of the normal bovine horn

Answer 1

composed of a sheath of keratin overlying a bony core
The surface of the bone is ridged and porous and is covered with papillated dermis that is continuous with the periosteum and epidermis which keratinises and forms the protective covering of the horn. The substance of the horn is similar to that of the hoof and is a mixture of tubules and intertubular horn. The new horn produced at the base is soft and often transparent and resembles the periople of the hoof, giving the horn a glossy appearance.

Question 2

describe the development of the normal bovine horne

Answer 2

• after 6 months of age, the bone becomes hollow and the space within is continuous with the frontal sinuses
• in the neonate, the bone portion is very small with a thin dermal and epidermal covering. removal of this covering will stop the horn from growing

Question 3

explain the structure of antlers

Answer 3

They consist of bony outgrowths from the skull with no covering of keratin as is found in true horns. Each antler grows from an attachment point on the skull called a pedicle. While an antler is growing it is covered with highly vascular skin called velvet, which supplies oxygen and nutrients to the growing bone; once the antler has achieved its proper size, the velvet is lost and the antler’s bone dies. This dead bone structure is the mature antler. Antlers shed after each mating season.

Question 4

what is the function of antlers

Answer 4

a display of strength to other males and potential mates

Question 5

list the differences between antlers and horns

Answer 5

• antlers are true bone, they grow as extensions of the skulls of deer
• horns are a 2 part structure (bony core and keratinized sheath
• antlers are shed annually, horns are permanent