Fainting Goat Facts

The goat that falls over when frightened

Tennessee fainting goat
The fainting goat has protruding eyes compared to a normal goat.

passion4nature / Getty Images

The fainting goat is a breed of domestic goat (Capra aegagrus hircus) that stiffens when startled. Although the goat may fall over and appear to faint, it remains fully conscious in a state of myotonia. Since it doesn't actually faint, the animal is properly known as the myotonic goat. Fainting goats have a hereditary disorder called myotonia congenita. Although the goat freezes when panicked, it suffers no harm and leads a normal, healthy life.

Fast Facts: Fainting Goat

  • Scientific Name: Capra aegagrus hircus
  • Common Names: Fainting goat, myotonic goat, falling goat, Tennessee goat, stiff-legged goat
  • Basic Animal Group: Mammal
  • Size: 17-25 inches tall
  • Weight: 60-174 pounds
  • Lifespan: 15-18 years
  • Diet: Herbivore
  • Habitat: Originally from Tennessee, USA
  • Population: 10,000
  • Conservation Status: Not Evaluated

Description

Fainting goats are a breed of small meat goats (heavily muscled). A typical adult ranges from 17 to 25 inches tall and weighs between 60 and 174 pounds. The breed has distinctive prominent eyes set in high sockets. While the most common fainting goat coat color is black and white, the breed occurs in most color combinations. Either long or short hair is possible, but there is no angora strain of fainting goat.

Group of fainting goats
Fainting goats come in a variety of colors and coat lengths. passion4nature / Getty Images

Why Fainting Goats "Faint"

All fainting goats have an inherited muscle condition called myotonia congenita or Thomsen's disease. The disorder is caused by a missense mutation of the CLCN1 gene that reduces chloride ion conductance in the chloride channels of muscle fibers. When the animal is startled its muscles tense up and don't immediately relax, causing the goat to fall down. Specifically, startling the goat causes its eyes and ears to send an electrical signal to the brain initiating the fight or flight response. When the response is initiated, the brain determines whether to stay or flee and the voluntary muscles momentarily tense.

In myotonic goats, the balance between positively charged sodium ions and negatively charged chloride ions is out of balance, so muscles have enough sodium to relax, but not enough chloride. It can take 5 to 20 seconds for the ion balance to resolve and the muscles to relax. The severity of the condition varies according to individual, age, water availability, and taurine supplementation. Younger goats stiffen and fall more often than older goats, in part because mature individuals have adapted to the condition and are less easily startled. Based on understanding of myotonia congenita in humans, it's known that the condition is painless and has no effect on the individual's muscle tone, consciousness, or life expectancy.

Fainted goat on ground
Young kids are more susceptible to fainting than older adults. Redleg / Wikimedia Commons

Habitat and Distribution

Fainting goats were brought to Marshall County, Tennessee, in the 1880s. Today, they are kept throughout the world, although they remain most numerous in the United States.

Diet and Behavior

Like other goats, fainting goats are herbivores that feed on vines, shrubs, trees, and some broad leaf plants. While goats taste most objects to gain information about them, they don't actually eat everything. Nightshade plants and moldy feed may be deadly to fainting goats.

Like other goats, this breed is naturally inquisitive. They are intelligent and can solve simple puzzles. Goat are social animals, but they will form herds with animals of other species, such as sheep, and can form close bonds with humans.

Reproduction and Offspring

Goats reach sexual maturity between the ages of 3 and 15 months, ideally when they have reached 70% of their adult weight. Females (does) come into estrus every 21 days and indicate willingness to mate by vigorous tail wagging. Males (bucks) curl their upper lips (flehmen response) and urinate on their forelegs and face to increase their odor. Gestation lasts around 150 days, usually resulting in twin births. Does start milk production when they give birth or kid. Domestic goats typically live 15 to 18 years.

Conservation Status

Because fainting goats are domestic, the IUCN has not evaluated the breed to assign a conservation status. However, the Livestock Conservancy lists it as threatened. According to the International Fainting Goat Association, there are around 10,000 fainting goats in the world.

Fainting Goats and Humans

Because of their rarity, fainting goats typically aren't raised for meat. The animals are usually kept as pets or show animals. Fainting goats are easier to care for than most other breeds because they are smaller, have a friendly disposition, and don't jump fences over 1.6 feet (0.5 meters) high.

Sources

  • Beck, C. L., Fahlke, C., George, A. L. Molecular basis for decreased muscle chloride conductance in the myotonic goat. Proceedings of the National Academy of Sciences, 93(20), 11248-11252, 1996. doi:10.1073/pnas.93.20.11248
  • Bryant, S. H. Myotonia in the Goat. University of Cincinnati College of Medicine, 1979.
  • Conte Camerino, D.; Bryant, S.H.; Mambrini, M.; Franconi, F.; Giotti, A. "The action of taurine on muscle fibers of normal and congenitally myotonic goats." Pharmacological Research. 22: 93–94, 1990. doi:10.1016/1043-6618(90)90824-w
  • Hegyeli, A., & Szent-Gyorgyi, A. "Water and Myotonia in Goats." Science, 133(3457), 1961. doi:10.1126/science.133.3457.1011
  • Lorenz, Michael D.; Coates, Joan R.; Kent, Marc. Handbook of Veterinary Neurology (5th ed.). St. Louis, Missouri: Elsevier/Saunders, 2011. ISBN 978-1-4377-0651-2.