My horse has recently started to cough. I just moved to a new barn, and one of the horses in a nearby stall had a cough. Now my horse has picked it up. But none of the other horses in the barn have it. The woman who owns the other coughing horse says he has had it for a couple years, and she doesn't know what is causing it. I'm worried it is something contagious and possible incurable. I don't think it is an environmental factor, because nothing about the environment is really any different from the old boarding facility. Any advice???