Fainting is caused by a genetic condition call
Myotonia congenita. The degree to which a goat exhibits myotonia is rated on a scale from 1-6, though the guidelines are general, they are as follows:
1. Never observed to stiffen,
but other type traits are consistent as is pedigree.
2. Very rarely stiffens,
3. Stiffens only
occasionally, and rarely falls.
4. Walks normally with no
swivel. The rear limbs lock up readily, the forelimbs less so, and goats with this degree of stiffness rarely fall to the ground.
5. Animal walks relatively
normally, although somewhat stiff in rear and with a swivel at the hip. Readily stiffens when startled or stepping over a barrier.
6. Animal always moves
stiffly to some degree, and readily becomes “locked up” when startled or stepping over a low barrier.
for more info on Myotonia
or Myotonic Goats please visit: http://www.myotonicgoatregistry.net/MGRbreeddescription/MGRBreeddescription.html
Fainting is seen most often in younger animals because, as they age, they learn coping
behaviors to help prevent falling over. In an adult that is startled, you will often see them start to lock up and then freeze in a saw horse type stance rather than falling onto their side. This is
their way of "preventing" the fall they know is coming when they feel their muscles tightening. Does the locking of the muscles "hurt"? There is no way to know for certain, but humans afflicted with
myotonia congenita report that is does hurt, like a severe muscle cramp that is uncontrolable. For this reason we try not to cause our goats to lock-up, but it still happens often for uncontrolable
reasons like the Livestock Guardian Dogs taking off barking, or a feed can lid being dropped.