Our poodle/mix has a rash near his crotch area and spreading. Help.?

I've not been able to find out what kind of skin problem this is. Can someone tell me,pls.|||Don't know what kind of rash either, but my little poodle had a rash on her back and I put some vaseline on it for two days, the rash is gone now. dogs do get rashes, it could be a flea or that the dog is biting at her butt. When you put the vaseline on watch her for a while so she does not lick it off too soon, it won't hurt her if she does lick it.|||Watery blisters? If so it's canine herpes. They sometimes get a little yellow pus-head on them. If it's a different type of a rash, then describe it.