Dogs snore for similar reasons that humans snore. They can snore simply because something is blocking their airway to some extent. There are lots of common reasons why something could block your dog’s air passages and result in him snoring:
Obesity: Being overweight or obese is very common in pets today. A dog that is overweight can have some breathing difficulties that make him snore. Put simply, small folds of fat can block the nasal passages. Or, when he breathes, especially while he’s sleeping, the rings in his trachea slap shut. The dog has to breathe harder, making the snoring sound, to draw breath.
Anatomy. Brachycephalic or short-nosed breeds are often prone to snoring. These breeds include Pugs, French Bulldogs, Bulldogs, and others with very short muzzles. They have shorter air passages than most dogs. If a sleeping dog has to breathe harder when he is dreaming or at some other point while he is asleep, he can start snoring.
Rhinitis. Dogs can snore if they have a temporary inflammation in their nasal passages or an allergy. An upper respiratory infection can also cause a dog to snore sometimes.
Foreign bodies. If your dog has a foreign body stuck in his nose, such as a blade of grass or a stick, it could make him snore. The foreign body could be blocking your dog’s normal breathing. A tumor in the nasal passage can have the same effect.
Fungal disease. Some dogs can snore because of a fungal disease called Aspergillosis. This fungal disease is the result of a mold found in the environment and on hay, grass clippings, and other vegetation. The fungus can cause serious health problems unless it is treated.
Dental problems. Dental problems can lead to infections. In some cases a bad tooth can push through the roof of a dog’s mouth into the nasal sinus passages. This will not only cause a dog to snore but it can introduce harmful bacteria into the dog’s body which can lead to serious health problems later.
Snoring is common in dogs and it’s often something minor that doesn’t bother your dog. However, in some cases it can be an indication of a more serious health issue. This is especially true if your dog suddenly begins snoring and he has never snored before. It’s a good idea to use your phone or camera to film your dog’s snoring so you can show it to your vet. Most dogs won’t cooperate by sleeping and snoring on command when you take them to see the vet so you can show your vet the video and ask him or her to evaluate your dog’s snoring. Your vet will probably also want to examine your dog’s nasal passages and mouth to make sure there are no obvious problems.
For some dogs, snoring does affect their quality of life. Pay attention to your dog’s snoring to see if he has any nasal discharge when he snores. Does he have any nasal bleeding? Is there any pattern to his snoring? Does he only snore at certain times of the year? If you can identify a pattern and there is watery discharge, your dog probably has an allergy. On the other hand, if your dog has any kind of nasal bleeding, he needs to see a vet right away for a diagnosis.