Dog breath. Or even cat breath, for that matter, is generally not a sign of fresh breath. But does it mean something more? Bad breath in your dog or cat can be a sign of halitosis, stomatitis, gingivitis, periodontal disease, mouth ulcers, gum inflammation, and abscessed teeth, to name a few things. If you have dealt with any of the symptoms above (or beyond) you will understand how important mouth health is to your pet.