Horses are coughing…

I have recently changed my horses to just add oats, weight check oil, bug check, and the pregnant mares to the previous plus preg check.  This problem is several weeks ago one of the pregnant mares started coughing. No fever, normal WBC.  I thought it was viral.  About a week later 5 of the 7 horses were coughing but not as bad as the 2 pregnant mares.  They are outside 14 hours per day and are currently not eating hay since they are all overweight and eating grass.  I finally gave all horses a course of SMZ antibiotics.  They are better but not normal.  I asked the local vet about heaves.  He did not think so since all seemed to get sick close together.  They initially had clear nasal congestion that turned yellow and is now clear.  I just want to make sure you do not think it has to do with all the powder type supplements.  Any suggestions?                       
Thanks, Renee

We have 10’s of thousands of horses on our supplements… never have we had an issue… In fact, they would help keep from such a problem from worsening…
And since it was probably viral,  the supplements would have/or probably did help the virus run its course perhaps even shorter. 
The antibiotics as you know are useless for viral and tend to mess up the gut and are honestly just one more synthetic issue the body has to deal with…   so, since they have been on an antibiotic please do consider our Gut Check to get it back in normal condition.

 I would also give the “Hi-Mag” version of our RED CAL free choice as well (if not already on). Feel free to call or email next time, before the drugs are considered… just might be able to and would be glad to, prevent the drugs.