Science, Tech, Math › Animals & Nature Fainting Goat Facts The goat that falls over when frightened Share Flipboard Email Print The fainting goat has protruding eyes compared to a normal goat. passion4nature / Getty Images Animals & Nature Mammals Amphibians Birds Habitat Profiles Reptiles Wildlife Conservation Insects Marine Life Forestry Dinosaurs Evolution View More Table of Contents Expand Description Why Fainting Goats "Faint" Habitat and Distribution Diet and Behavior Reproduction and Offspring Conservation Status Fainting Goats and Humans Sources By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated July 08, 2019 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 hircusCommon Names: Fainting goat, myotonic goat, falling goat, Tennessee goat, stiff-legged goatBasic Animal Group: MammalSize: 17-25 inches tallWeight: 60-174 poundsLifespan: 15-18 yearsDiet: HerbivoreHabitat: Originally from Tennessee, USAPopulation: 10,000Conservation 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. 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. 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.93.20.11248Bryant, 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-wHegyeli, A., & Szent-Gyorgyi, A. "Water and Myotonia in Goats." Science, 133(3457), 1961. doi:10.1126/science.133.3457.1011Lorenz, 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.