Sounds like you have an air quality issue.
In all my years of having horses( boarded and home) and even working at several barns and being there all day, there is no smell on anything that I could detect except my clothes and footwear.
If you smell like the barn I bet you have a lot of ammonia and wet floor issues. Are they on concrete in the stalls? That sweats and can be unpleasant all on its own.