Nursing Dog Has Rash and Pimples

Question
My nursing dog just developed a rash with pimple like growths around her nipples. Have you ever heard of anything like this?
I took her outside and washed the area, but I don't know what else to do. Is peroxide a bad idea to put on the pimple like things? Should I extract the puss? Do you think it is serious

Answer
I would need to know how old and big the puppies are. Some times when the pups are too big and start growing teeth it may irritate the nipples, puppies can be weaned at 4 wks old. Keep the irritated area's clean and dry, peroxide should be fine if you rinse with water afterwards. If the puppies are not old enough to wean then you may have to take mom in for antibiotics and buy mother's milk from a pet store, if her nipples are infected by bacteria you don't want the pups mouth to get infected. Sincerely Concerned, Angela