Treatment of COPD in horses.
This summer, my mare was diagnosed with COPD. I've had her for going on four years, and we've never had problems before this. She was coughing really bad, with some heavy breathing. The vet said that because of the drought we had this summer, everthing was much more dusty than usual, and probably triggered the COPD. He also said that she may be fine in the winter, or even next summer- it all depends. We put her on an antihistamine- which the vet said that she could be on long term- and had her on Theophylline pills, but those aren't meant for long term use. We are also wetting down her hay.
What I'm wondering is if there is anything else I can do for her. She does still cough occasionally. We do some light dressage work, and when I start riding her at the trot, she'll start coughing. However, my trainer witnessed it, and said that that was okay- she needs to cough out whatever is in her lungs, and the exercise will improve the blood flow, open air passageways, etc.
She is NOT kept in a stall- she has a three and a half sided run-in shed, and is usually out in the paddock, poking around in the dirt for food- which explains all the dust in her lungs.
I just feel like I'm not doing enough to help her, and I'm terrified that there will be long-lasting damage. Thank you for any and all help!