I know with my girls and guys, if I am cleaning out water tanks and its nice and hot out, I turn the hose on them, since they always are so nosey to see what I am doing... once the water hits them, they will run out of the way so they dont have to get wet. They must think they will melt too. I also noticed mine wont roll in mud, but they will stand out in the rain, if its a nice light rain, but if its a heavy downpour ...there out of there!
I dont use a spray on my donkeys, I have a soft brush that attaches to the hose and I just let the water trickle on them and eventually turn the water on full. I dont use cold water, but warm. They HATE cold water, but seem to stand alot better if I use warm. ALot of times its the hose that they are terrified of. They seem to think its some big green snake that is going to "get them", once they are use to the hose moving around, it makes things alot easier.
Corinne