Can Horses and Dogs Get PTSD?

My sister's dog Lana

Approximately 5% of the military dogs serving in the US armed forces suffer from Post Traumatic Stress Disorder (PTSD).  If the dog cannot be cured, it will be retired from active service. 

Signs of PTSD disorder in military canines is shown by a variety of symptoms such as listless behavior, barking at gunfire that the  dog previous met with silence, and running away from certain situations.

"More serious cases will receive what Dr. Burghardt calls "desensitization counter-conditioning," which entails exposing the dog at a safe distance to a sight or sound that might trigger a reaction—a gunshot, a loud bang or a vehicle, for instance. If the dog does not react, it is rewarded, and the trigger—"the spider in a glass box," Dr. Burghardt calls it—is moved progressively closer until the dog is comfortable with it."

Source: http://news.yahoo.com/blogs/sideshow/military-dogs-taking-xanax-receiving-therapy-canine-ptsd-222819057.html

So what does this have to do with horses you might ask?  Temple Grandin, an animal behaviorist, in her book Animals Make Us Human discusses how rough training methods may ruin a horse.  She compares "sacking out" or the exposure of a horse to all manner of new things all at once to overwhelming or "flooding" a horse with new stimuli.  All horses react with fear--some adjust but some do not and are traumatized.  As Grandin states:

"It's a horrible thing to do to a horse.  The hot-blooded Arab-type horse, you traumatize and wreck.   I think you get a post-traumatic stress disorder (PSTD) effect, similar to a traumatized war veteran.  A horse treated this way can't be ridden.  A less reactive horse, like a quarter horse from a bloodline that's really calm, can take it, but it's still a bad thing to do."  (p. 108)

Grandin recommends habituating horses gradually to new and strange stimuli similar to what Dr. Burghardt calls "desensitization counter-conditioning."

Source: Grandin, T.  (2009).  Animals Make Us Human, First Mariner Book, NY.