Most yearling goats have horns about six inches long, which at a casual glance look much like adult horns. By the time a goat is four years old its horns are 8-9 inches long. The world' s record mountain goat, a male killed in British Columbia in 1949, had 12 inch horns. Although horn lengths are difficult to discern, other horn characteristics can be used to differentiate between the two sexes. Males have heavier horn growth, with a greater basal diameter and greater diameter along the entire length of the horn.
Female horns are thinner and less massive appearing.
Unfortunately, this difference is difficult to distinguish except in larger adults at very close range. Horn curvature usually differs significantly between males and females. Males exhibit a smooth, even curvature throughout the entire length of the horn. In contrast, horns show their greatest curvature near the tips. This virus is contained in dark brown or black scabby lesions around the eyes, nose, muzzle, ears, or sex organs of goats and sheep.