When should I worry about a cough

Now that Cinny and I have found our better fitting saddle, an arena with better footing, and a great bit...we have been actually "working" instead of merely riding. He has sat pretty much all 7 years of his life until a month and a half ago. He wasn't ridden until about 3 weeks ago...and it was pretty much just riding to get him started, not actual work.

Well now that we are actually "working" it seems he coughs a LOT. What I mean by working is lunging...5 turns at a good pace walk, then 30 at a trot..each direction. I am counting times because I want to make sure he doesn't get stronger on one side than the other..is this silly? I haven't been cantering on the lunge line so much, just the walk trot. Towards about the 25th time around or so he starts to slow down his pace. In the second direction he will slow down then start really stretching his neck out and cough..and not the usual cough cough from dust or just warming up, he rattles the windows and mirrors in the arena.

Then when I ride I go about 3 times each direction at a walk, bending and doing circles in each corner, each direction. Each time around I give him a little more squeeze to push him more into the bridle..with an extremely loose rein. Then we work the trot, again working on circles and bending in the corners. About this time he starts doing the stretching and the window rattling cough again...but instead of just one to three times like in lunging, he does it consistently over and over for about 5 minutes or so, it almost seems like horsey athsma. After going about 5 times each direction at a trot I do about 5 figure eights to get him used to changing diagnals...and sometimes he is still coughing at this point. It sort of comes and goes. Coughing for about 5 minutes then no cough, then coughing again.j

I ride in an indoor arena that is dragged daily and they gently mist it early afternoon before the "rush hour" begins so there usually isn't much dust flying. He is in a dry lot with a round bale. He only coughs when being worked.

Does this sound like the typical "out of condition" cough or does it sound like something worse? And how can you tell if it's just a lack of conditioning? Are there supplements that will help him? He currently is getting Nu Image, MSM (to help with the swelling and itching of the nasty fungus he had), Farriers Formula II, and smart vite. None of the other horses at the stable seem to have this issue.

Thanks for reading this...and your suggestions.

It *could* be heaves or asthma-related issues. When my vet was failing my horse before his free adoption (haha) that was one of the things he was concerned with because he had a cough when exercised and a lot of noise in his lungs and throat.

It actually turned out to be nothing and when he came back to give him the medication (after I adopted... owner wouldn't pay for it) it turned out he didn't need it anymore!

If it persists it may be worth having someone take a listen inside and see what's going on in there. It could be allergies or the dust. Also, I think he told me that heaves and issues like that can be seasonal and we were worried that the spring/summer was what triggered his coughing where there had been none before.

I hope it's just allergies or dust, although the new place is surprisingly almost dust free they keep it so darn clean, lol. Maybe they keep it too clean...if that's possible. I think I also heard the BO complaining about the quality of the round bales she purchased last time and was saying that she upped more $$ for a better batch from a different grower so maybe that will be the only change he needs, besides a lot of conditioning work.

It's just really hard to tell how hard to push a horse into conditioning when you don't know if their cough is lack of condition or dust/allergies...hmmmm.

I skimmed, so sorry if I missed something. My mare coughs when she's working well, I.e. Is collected. We warm up doing lots of lateral work, flexion, collection, etc at the walk. Then we start trotting, she always has to cough. BUT she never coughs if I don't do a good walk warm up.