Fainting goats

A fainting goat is a breed of domestic goat whose external muscles freeze for roughly 10 seconds when the goat is startled. Though painless, this generally results in the animal collapsing on its side. The characteristic is caused by a hereditary genetic disorder called myotonia congenita. When startled, younger goats will stiffen and fall over. Older goats learn to spread their legs or lean against something when started, and often they continue to run about in an awkward, stiff-legged shuffle.
Slightly smaller than standard breeds of goat, fainting goats are generally 43 to 64 cm (17 to 25 inches) tall and can weigh anywhere from 27 to 75 kg (50 to 165 pounds). They have large, prominent eyes in high sockets, and exist in as many colors as standard breeds do. Hair can be short or long, with certain individuals producing a great deal of cashmere during colder months. There appears to be no angora strain of the fainting goat.
The origin of the fainting goat is peculiar. The goats appear to have arrived in Marshall County, Tennessee in the early 1800s, courtesy of a reclusive farm worker named Jon Tinsley who was most likely from Nova Scotia. Before he left the area, he sold his goats — three does and a buck — to Dr. H.H. Mayberry, who bred them.
Fainting Goats have many other names, including Tennessee (Meat) Goats, Nervous Goats, Stiff-leg Goats, Wooden-leg Goats, and Tennessee Scare Goats.

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