A dog’s mouth has copious amounts of bacteria that contribute the bad breath (halitosis) they have. Along with the bacteria, if your dog enjoys eating foul things well then obviously their breath will stink all the more. So one of the ways to determine what the cause of the noxious odor escaping from your pet’s mouth is to determine what they have eaten. If you notice that they have not indulged in cat poop or the like, then take a good look at their teeth and gums and assess whether or not a visit should be paid to the veterinarian.