Dogs seldom have kidney stones, but bladder stones are common in dogs. In most cases, the stones are in the bladder, but sometimes some of the stones may pass into the urethra.
If a stone is large enough, it can cause a blockage which is extremely serious and requires immediate veterinary attention.
Dog bladder stones vary in sizes and number.
All dogs can develop bladder stones but some breeds are more prone to this condition. These breeds include:
- Bulldog
- Dachshund
- Dalmatian
- Miniature Schnauzer
- Shih Tzu
There are different types of bladder stones in dogs. They include:
Struvites
Struvites are the most common type of bladder stones in dogs. They are composed of magnesium ammonium phosphate. These stones form in an alkaline urine. They are usually the result of a bladder infection, which causes the urine pH to raise to neutral or alkaline.
Female dogs are more prone to bladder and urinary tract infections, so they are more susceptible to struvites as well.
Calcium Oxalate Stones
These are the second most common canine bladder stones. These stones are seldom the result of bladder infections. Instead, they are mostly the result of increased levels of calcium in the blood stream.
Dogs with a certain hereditary condition are prone to calcium oxalate stones. The dogs lack a calcium-binding glycoprotein called nephrocalcin that inhibits the growth of calcium oxalate crystals in the urinary tract.
Uric Acid Stones
These stones form in an acid urine. They are found almost exclusively in Dalmatians and Bulldogs because their livers cannot absorb uric acid.
Causes of Bladder Stones in Dogs
There are many possible causes of canine bladder stones, such as:
Diet
Improper diets can easily cause bladder stones in dogs. For example, a high-protein diet with excess amounts of magnesium, calcium, or phosphorus can lead to stone formation in dogs.
Water Intake/Output
Dogs who do not have sufficient water intake or who cannot go out to urinate frequently enough are more susceptible to bladder stone formation.
Bladder Infections
Bacterial bladder infections can lead to the formation of struvite bladder stones.
Age and Gender
Older dogs tend to be more prone to bladder stone formation. Female dogs are also at higher risks because they are more susceptible to bladder infections.
Exposure to Cadmium
Studies have found that exposure to cadmium will lead to an increased chance of bladder stone formation. The most common source of cadmium exposure for dogs is cigarette smoke.
Symptoms and Diagnosis
The typical symptoms that a dog has bladder stones are frequent, painful urination and blood in the urine.
Dribbling urine indicates that there may be a partial blockage of the urethra.
A vet makes a diagnosis of canine bladder stones by analyzing a urine sample. He also uses X-ray or ultrasonography. Sometimes, he can even palpate through the abdomen if the stones are large enough or if there are numerous stones.
Treatment of Bladder Stones in Dogs
Treatment depends upon the type, size and number of the stones.
If the bladder stones are formed as a result of a bladder infection, treating the infection first using antibiotics is necessary. These stones (struvite stones) can then be dissolved by feeding the dog a special diet that is low in magnesium and protein.
For uric acid stones, a low-purine diet can dissolve the stones together with the drug “Allopurinol”.
However, a low-purine diet is not appropriate for puppies. If a growing puppy has uric acid stones, removal by surgery is probably a better choice.
There are no methods that can be used to dissolve calcium oxate stones. Surgical removal is usually necessary. After that, dietary supplements can be given to the dog to prevent recurrence.
Surgical removal is also necessary for stones that cause urethral obstruction, and for stones that fail to respond to medication and/or dietary change.
Supplements to Prevent Bladder Stones in Dogs
Supplements can be used to prevent bacterial bladder infections and stone formation:
- Cranberries: Cranberries (also blackberries and raspberries) are effective in preventing cystitis because they help to prevent bacteria from adhering to the lining of the bladder and the urethra. They may also help to lower urine pH.
You can give non-sweetened cranberry juice (about half an ounce for dogs) to your dog, or you can use a cranberry powder product such as cranberry powder or a chew treat.
- Vitamin C: Vitamin C can acidify the urine which in turn helps to control bacterial infections. Vitamin C also has anti-inflammatory properties and therefore can prevent infections.
- Cod-liver oil: Cod-liver oil is rich in vitamin A which is essential in keeping the lining of the bladder and urinary tract in good condition.