Hi Don,

As per the other comment it does seem to me like your TB is getting a little over excited or stressed.

As an owner in a racehorse syndicate I recently took our TB when it reached the end of its career. They really are delicate animals who do find it difficult going from a very regimented regime, out on the gallops every day and being in their box for most of the day (if they're out they can get injured) to a life of leisure. This is hard. I really would get expert help before attempting to ride yourself. They can appear lazy, but this is because they are use to being "worked" in a very specific way. Give it some time to relax, getting used to being a horse and it will pay off.

In terms of generally keeping a horse cool there are some good horse rugs and blankets out there which wick away any sweat and during those hot summer months keep the dangerous rays of the sun off them. For some pale and sensitive horses sunburn can be a real problem.