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A dog’s oral health is as important as its physical health. Many vets determine how healthy a dog is just by inspecting its mouth. If it has big, white teeth, pink, moist gums, and clear saliva, it is deemed to live a long, happy life.

The mouth is more than a woofer for vocalization. With the help of their mouth, dogs regulate their appetite, playfulness, and love for their humans. Since most of their activities involve their mouth, it can easily become the breeding ground for many infections. They can develop chronic mouth inflammations and ulcers, which can hinder growth and make the dog unfit for many physical activities. It makes the dogs lethargic, lose their appetite, and develop halitosis and swelling.

Getting to know the causes of these mouth sores will help you take better care of your dog and enjoy the time together with it. The basics might even help save your dog’s life altogether.

Mouth sores are quite common among dogs. As dangerous as they may be, knowing the root cause of the disease can aid in getting rid of the problem once and for all. Below are some of the causes of this symptom:

1. Weak Immune System

Mouth sores are one of the worst conditions in dogs. They may be an indication of a serious underlying disease which may have triggered the virus. Pemphigus is a skin disease which weakens the dog’s immune system, and the connections between the skin cells are attacked.

This disease is usually caught through infection or a virus. It can be a reaction to a drug, be caused by the dog’s breed or be a genetic predisposition. As a result, mouth sores and ulcers may appear on the skin of the dog. If the condition is not tended to immediately, it may result in life-threatening disease.

Small or young dogs have a naturally weak immune system. They have trouble digesting food, and not every meal suits their diet. The owner must consult the vet before including any new food into their pet’s diet. The new food must be slowly introduced by mixing it with the old one. Abrupt changes in the diet can cause the immune system to react and diseases like ulcers and mouth sores to develop easily.

2. Nutritional Deficiencies

The diet of your dog determines its health. Riboflavin is an important vitamin present in dog food, which provides the necessary nutrients responsible for keeping the dog healthy. A raw diet such as organs and muscles, egg yolks, fish and beef have this vitamin in high quantities. If this vitamin is missing in the diet, the dog is likely to feel weak and experience hair loss and anorexia. One of the most obvious signs of riboflavin deficiency is the presence of mouth sores.

Another nutritional deficiency can be from the lack of proteins and calories. Your dog may not be ready to become a vegetarian yet. Meat is extremely important for a dog. Beef, chicken, liver and other organs must be included in its diet. One of the companies that make Freeze-Dried Raw Dog Food is TruDog. I strongly recommend you to try them. A raw diet has a lot of benefits like supporting the immune system, helping maintain a healthy weight, and is easy to digest.

3. Viruses and Infections

The occurrence of mouth sores is the first sign of a virus or an infection in the dog. It acts as a cautionary signal for the owner to get the dog checked urgently. Dogs may get leptospirosis from drinking contaminated water, food or a bite of an infected insect. Sores can also result from any periodontal disease, which may affect the tissues surrounding the mouth. These viruses weaken the immune system and harbor bacteria in the mouth, which destroy the tissues that support the teeth. Sores hinder the everyday activity of the dog and small tasks such as eating or playing games.

4. Traumatic Reasons

Another cause of mouth sores among dogs is a disturbance between the chewing and biting surfaces, i.e., the upper and lower teeth. The pressure put on the teeth to chew and the muscles around the face can cause mouth sores to develop, making it even more difficult to eat the food.

Another reason is chewing on broken wood fragments or any kind of electric cord. Special attention must be paid to where the dog might be playing and the areas it might be snooping around in.

5. Chemicals or Acids

The dog may have come in contact with harmful chemicals or acids, which may have reacted in the dog’s mouth, causing ulcers and mouth sores. Thallium is the most common cause of sores. This element is found in tins and cans. Extra care must be taken as to where the dog is playing and what it is playing with.


When the first sores appear in your dog’s mouth, proper medical attention must be given immediately to prevent serious diseases. It must never be taken lightly. If the dog is sulky and has bad breath, swollen gums, a plaque on teeth or appetite loss, the chances are that it might be getting mouth sores.

In order to treat the sores, the plaque must be removed from the surface of the teeth. Any tooth significantly damaged must also be removed to prevent the sores or ulcer from spreading. Prescribed antibiotics prove to be useful in treating the sores. Moreover, special attention to the diet must be given. Foods containing high calories and nutrients must be included in the diet.

A part of the cure of the disease lies in the vigilance of the owner. The owner must take extra care of the hygiene of the dog. Its teeth must be cleaned twice in a day along with frequent oral rinses and gels to remove the plaque.

If proper attention and care is not given, these sores may develop into cancer or tumors. However, with early antibiotics and treatment, the sores can be easily treated. With a little precaution and care, mouth sores will be gone in no time.