Some breeds are more susceptible to bad breath than others, and others are at a higher risk for periodontal diseases. Smaller breeds such as toy dogs are often at higher risk for diseases of the mouth. This causes bad breath for dogs.
This is because toy breeds, while smaller than the traditional breed, still need to fit the same amount of teeth into their smaller jaws. The teeth are more compact and therefore ideal places for bacteria to grow and hide.
Dogs with thinner muzzles might also be more prone to bad breath due to the higher risk of dental diseases. Greyhounds and whippets fit into this category.
Bear in mind that even though your dog might not be a toy breed or have a thin muzzle, they can still suffer from dental problems or bad breath. If the change of diet doesn’t rectify the issue, get a veterinarian’s attention.