I agree it could be an allergic reaction - that's what my pit bull/boxer has right now but I think it was some weeds that set it off.

It might just be bug bites too though if they were outside - depending on how many spots there is.
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I actually shower with both of my dogs rather than giving them a bath. One is a pitbull/boxer mix and the other is a pitbull/mastiff(I think). They do just fine in there with me. Due to their breeds they don't need baths very often and it's faster to...