How do these 7 conditions cause bad breath? Here are the explanations.
In one study, bad breath was noticed 1.2 years before recognition of chronic kidney disease by veterinarians. It would seem to be an early symptom which can be added to weight loss, decreased appetite and excessive drinking. It’s interesting to note that I can’t find the precise chemical process within the body which causes bad breath because of the existence of chronic kidney disease. Obviously, the kidneys fail to remove the waste in the blood stream and it therefore builds up. The bad breath may have an ammonia odour. That’s indicative of the fact that the waste products in the bloodstream are noticeable in the breath of the cat. It would seem that the smell of the waste in the blood leaks into the gut and/or lungs and mouth. That’s about as good as I can do to explain what’s going on.
Diabetes is high blood sugar levels in the blood. This increases glucose levels in saliva which provides food for bacteria in the mouth which in turn leads to a buildup of dental plaque and also in turn this leads to tooth decay and gum disease and halitosis.
A similar causal effect to bad breath occurs with liver disease. Livers filter toxins out of the body. A malfunctioning liver fails to do this. Toxins build up such as sulphur causing a condition labelled Fetor hepaticus in humans. It’s different to normal bad breath. It smells like sulphur and is a direct result of liver disease. The patient’s breath contains dimethyl sulphide causing the bad breath. Essentially, waste products remain in the blood and that has the effect of the air expelled from the body containing some of these products.
A tooth abscess causes bad breath because a pass-filled pocket of bacteria develops at the root of the tooth which smells as it leaks.
Gum (periodontal) disease
In the case of periodontal disease-causing bad breath, the smell comes from the bacteria growing below the gum line (sub-gingival dental plaque) which has a foul smell and which, therefore, obviously causes or contributes to bad breath.
With respect to gut problems, a gut infection or blockage can make the breath smell bad and there will be other likely signs such as vomiting and diarrhoea. The smell from the blockage comes up the digestive tract into the mouth which is expelled when the cat breeds. That is also my interpretation.
Cancers of the mouth
My understanding is that cancers per se can produce a specific smell. The smell may vary between different cancers. The smell is caused by cancer specific chemicals. If the cancer is in the mouth it’s going to cause the breath to smell. I can remember a cat in a residential care home in America whose name was Oscar who was able to detect when a patient was dying because of cancer by the smell emitted from an individual.
Below are some pages on oral health, a major issue in middle-aged and elderly domestic cats.
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