Horn (anatomy)

A horn is a living, vein and artery filled, pointed projection of the skin of various animals, consisting mainly of keratin as well as other proteins. True horns are found only among the ruminant artiodactyls, in the families Antilocapridae (pronghorn) and Bovidae (cows, buffalo, yaks, goats, antelope etc.). Those animals have one or two pairs of horns, which usually have a spiral shape.
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