How To Make My Dog's Breath Smell Better Diy . 2 tablespoons extra virgin olive oil. The citric acid present has the ability to kill bacteria and neutralize the release of sulphur compounds both in water and in the dog’s mouth. Pin on Dog Health Tips from www.pinterest.com Preventing bad breath in dogs. Shampoo the outside of the ears, the legs, the chest, belly, featherings (if any), and the rest of the body. Simply squeeze a few drops of lemon juice into your dog’s water.