Two stones, two completely different plans
Most canine bladder stones are one of two types, and the difference is far from academic. It decides whether your dog can avoid surgery, what they eat afterwards, and how likely the whole thing is to happen again.
| Struvite | Calcium oxalate | |
|---|---|---|
| Chemical name | Magnesium ammonium phosphate | Calcium oxalate monohydrate / dihydrate |
| Urine pH | Forms in alkaline urine | Forms in acidic urine |
| Common trigger | Urinary tract infection | Metabolic; breed predisposition |
| More common in | Female dogs | Male dogs, small breeds |
| Dissolves with diet? | Often, over several weeks | No, never |
| Treatment | Diet + treat infection, or surgery | Surgery |
| Prevention | Prevent and treat UTIs, targeted diet | Urine-diluting diet, high water intake |
Struvite: the one you might avoid operating on
Struvite stones in dogs are usually a result of a urinary tract infection. Certain bacteria produce an enzyme that raises urine pH, and in that alkaline environment magnesium, ammonium, and phosphate come out of solution and clump together.
Because the cause is chemical rather than structural, removing the cause often removes the stone. A dissolution diet acidifies the urine and cuts the mineral supply, and antibiotics clear the infection. Over several weeks, many struvite stones disappear completely.
Consider a typical example. A six-year-old female spaniel in Talleyville starts having accidents and leaving pink spots on the kitchen floor. Urinalysis shows infection and struvite crystals, and X-rays show two medium-sized stones in the bladder and nothing in the urethra. She goes onto a dissolution diet with antibiotics, and repeat X-rays at four and eight weeks show the stones shrinking and then gone. No surgery needed.
The caveats are real, though. Dissolution takes weeks, during which your dog still has stones and may still be uncomfortable. It demands strict dietary discipline: no treats, no table scraps, nothing else in the bowl. And it is not appropriate if a stone is large enough to risk blocking the urethra as it shrinks.
Calcium oxalate: surgical, without exception
Calcium oxalate uroliths form in acidic urine and, unlike struvite, no diet will dissolve them. Once they exist, surgery is the only way out.
Now picture a nine-year-old male miniature schnauzer from a nearby street with the same symptoms. His urine is acidic, with no infection, and X-rays show a cluster of small, very bright, spiky-looking stones. That combination points strongly to oxalate, so the plan is a cystotomy within days, followed by a urine-diluting diet once the analysis confirms the type.
Oxalate stones are more common in male dogs and certain small breeds, and they have become the more frequent type in recent years, partly because diets designed to prevent struvite acidify the urine, which shifts the risk toward oxalate.
Because they cannot be dissolved, prevention after removal matters more for oxalate than for any other stone. The strategy is dilution: a diet that increases water turnover and lowers urinary calcium and oxalate, plus every practical way of getting more water into your dog.
Same symptoms, opposite treatments.
This is exactly why removed stones are sent for analysis. Prescribing a prevention diet without knowing the type is guesswork, and guessing wrong can speed up the next stone rather than prevent it.
Practical prevention, whichever type
Water is the common factor. Dilute urine cannot become saturated, and saturation is where every stone starts. Several water bowls, a fountain if your dog likes moving water, and wet food or water added to dry food all help.
Frequent urination. A dog who holds urine all day while the household is at work concentrates it and gives crystals longer to clump. More toilet breaks genuinely reduce risk.
Stick to the prescribed diet. Therapeutic urinary diets are precisely formulated. Treats, chews, and scraps undo that, and owners are often surprised how much a single daily biscuit matters.
Periodic urinalysis. A returning infection or a pH shift shows up in a urine sample long before a stone shows on an X-ray.
If your dog already has stones
Bladder stone surgery through Talleyville Dog Surgery starts at $950 and is normally booked within days. Stone analysis is quoted separately, and it is the add-on we recommend most consistently, because it is the difference between treating this episode and preventing the next.
If your dog is straining and producing no urine at all, that is an emergency. Go to the nearest emergency hospital immediately.