It just seems that the heat makes his respiration higher. When I asked the vet if I could still ride him he said yes, but don't get him hot and sweaty. Since you can't ride right now for 5 minutes without the horses getting hot and sweaty, even in the early morning, I'm giving him the time off. Remember one day last week he was sweating just out grazing, he didn't do that yesterday, and it seemed hotter.
The other horses with the exception of Rocky all stand out in the sun even tho they have shade available. Rocky goes in.
Becky
OK - I think probably the most important part of the vet's warning was probably against the ~work~ and huffing and puffing that would make him hot and sweaty.
If he wants to stand in the sun when he has shade available, I am not sure I'd put him in just to get shade.... For his lungs I'd worry more about the dust in those hot corners they like to stand in. Maybe hose that area down, or maybe, with all your rain dust isn't a problem.