My dog recently started rolling in poop. Not his own poop, but other animal's poop he finds outside. This is not something I can let happen. I've been very careful not to let him do it after the first couple of times, but I cannot quite get the stinky smell off him. I have given him several baths with oatmeal dog shampoo and brushed his teeth, but there is still a faint odor of poo. How can I get this poopy smell off him for good?