Poor Zimmy. There's no blanket or harness on his back - just pure unadulterated sweat. And not even the "I've been hard at work" or "I've just been ridden w/ a saddle and blanket on my back" kind of sweat. Just plain "I'm standing here in the pasture minding my own business" sweat.
Due to his darker coat color (and I'm sure a bit has to do with his full-figuredness) he sweats a lot when there's temps in upper 90s-100s and not enough breeze to counteract the sun.
Yes, I gave him a shower this afternoon to clean the salt out of his pores and get the dirt out of his hair.