Meant to add that I have been tracking his respiration rate (just by watching his breathing) and it seems within the normal range - 10 - 13 breaths per minute (it’s surprisingly hard to count breaths for a full minute).
I’d bed it with pellets if you’ll wet them down.
Thanks, that’s what I’m leaning to. This time of year it’s easy, just drag the hose in there. Winter I don’t know, but maybe dip watering cans out of their heated water trough. Or go back to shavings since they’re in more by choice and the bedding will be turned over more often.
This guy was supposed to be a btdt low maintenance fellow 
Good thing he’s pretty much perfect in all other regards.
My guy lives out 24/7 and I thoroughly wet his hay down. He’s also on SmartBreathe for what that’s worth. 10cc of oral dexamethasone and 10cc ventipulmin set him right if he really does flare.
Went with the bedding pellets. I’ve gone back and forth using them over the years, I think this is going to work. I just need to get my head wrapped around wasting “clean” bedding that is clean but maybe dusty, and watering it daily.
When I’m super diligent with all of the measures (soaking hay, immersing in water, not just hosing it) and now the bedding he is greatly improved. Still the odd cough but the runny nose stops and his breathing doesn’t look laboured at all.
Always something with these horses! I’m coming to the conclusion that a truly maintenance-free horse doesn’t exist.
