Short answer: Dalmatians carry a genetic mutation that makes them excrete uric acid instead of converting it to a soluble waste product, which raises their risk of urate stones. The Merck Veterinary Manual lists a low-purine diet, more water in the diet and less acidic urine as the key tools for preventing and dissolving these stones, with medication added by a vet when diet alone isn’t enough.
Dalmatians carry a genetic quirk unique among dog breeds: a mutation affecting how they metabolize uric acid, causing them to excrete significantly more of it than other breeds. This raises their risk of urate stones forming in the bladder or kidneys, making diet a more central part of this breed’s routine health management than for almost any other breed.
Why Do Dalmatians Have This Specific Urinary Risk?
In most dogs, uric acid, a product of purine breakdown, is converted in the liver to allantoin, which is soluble and passes easily in urine. That conversion is reduced in Dalmatians, which excrete most of these waste products as relatively insoluble urate. The cause is a mutation in the SLC2A9 gene, which encodes a uric acid transporter; the same mutation has been found in some English Bulldogs and Black Russian Terriers.
It is a breed-wide trait. The researchers who identified the gene, Bannasch and colleagues, reported in 2008 that all Dalmatians are homozygous for it, meaning they carry two copies. The exception is a line of Dalmatians descended from a Dalmatian × Pointer cross, created specifically to reintroduce the normal version of the gene into the breed. The researchers note the trait was probably fixed in the breed through selection for its distinctive spotting.
Carrying the trait isn’t the same as getting stones, though. Diet, water intake and urine concentration all affect whether urate actually crystallizes.
What Dietary Changes Help Manage This Risk?
- A low-purine diet. Purines break down into uric acid, so less purine means less urate in the urine. For a dog with a stone history, this is usually a veterinary therapeutic diet; ask your vet which foods and treats to limit.
- More water in the diet and in the bowl. Merck lists increasing dietary water content as a key part of treatment, because dilute urine gives urate less chance to crystallize. Wet food, water added to kibble and several water bowls all help.
- Less acidic urine. Urate is more soluble when urine pH is above 7, and therapeutic diets or supplements your vet prescribes (such as potassium citrate) are used to raise it.
- Moderate, high-quality protein rather than protein-heavy extras, since dietary purines come mostly from animal sources, as the NIH’s arthritis institute notes in its guide to gout, the human condition caused by the same uric acid.
How Is a Dalmatian With Stones Treated?
Stones can sometimes be dissolved rather than removed. According to Merck, dissolution relies on raising urine pH above 7, increasing water intake and feeding a low-purine diet, and complete dissolution has been reported in Dalmatians about half the time, typically within about a month. Vets may add allopurinol, a drug that reduces uric acid production, but Merck warns that “strict adherence to a low-purine diet must be maintained” while it’s used, because the combination of allopurinol and a purine-rich diet can cause a different stone type (xanthine). Never give it without a prescription.
Stones that block the urethra, or that don’t dissolve, need removal. Because urate stones are highly recurrent in dogs with this trait, Merck advises ongoing prevention with a low-purine diet, sometimes with urine-alkalinizing supplements, and periodic imaging for dogs that re-form stones often.
| Situation | Typical diet approach | Monitoring |
|---|---|---|
| Healthy Dalmatian, no stone history | Complete and balanced food with moderate protein; plenty of water; few rich extras | Urinalysis at routine checkups; watch for urinary signs |
| Urate crystals found in urine | Discuss a lower-purine diet and more water with your vet | Repeat urinalysis as your vet advises |
| Past urate stones | Veterinary low-purine diet, higher moisture; urine alkalinizer if prescribed | Regular urine tests and imaging to catch new stones early |
| Stones present now | Dissolution protocol or removal, directed by your vet | Frequent rechecks until clear |
How Should Owners Approach Feeding a Dalmatian Day to Day?
- Choose a complete and balanced commercial food with moderate protein, and keep treats small; AAHA suggests treats make up no more than 10% of daily calories
- Encourage water intake throughout the day — a water fountain, multiple bowls or water added to meals can help
- Avoid feeding rich, protein-heavy treats and table scraps, and check any new treat with your vet if your dog has had stones
- Watch for signs of urinary trouble (straining, blood in urine, frequent small urinations) and treat them as urgent, given this breed’s known risk
- Give plenty of chances to urinate; Merck notes stones only form when crystals stay in the urine long enough
- Discuss preventive dietary strategy with your vet even before any symptoms appear, given how universal this genetic trait is across the breed
If you’re comparing foods, our guides to reading a pet food label and judging dog food brands explain what the label can and can’t tell you.
What Are the Warning Signs of a Urinary Stone?
The Merck Veterinary Manual’s owner guide to urinary disorders lists painful urination, blood in the urine and slow or difficult urination as signs of stones in the lower urinary tract. A dog that keeps trying to urinate but produces only small amounts, or none, may have a stone blocking the urethra. That is an emergency: a blockage lets toxic wastes back up and can damage the kidneys. If you’re unsure whether your dog is uncomfortable, our guide to recognizing pain in dogs covers the subtler signs.
This article is for informational purposes only and does not replace guidance from your veterinarian.
Sources
- Merck Veterinary Manual — Urolithiasis in Dogs, February 2026
- Merck Veterinary Manual (Pet Owner Version) — Noninfectious Diseases of the Urinary System in Dogs, May 2026
- Bannasch D, et al. — Mutations in the SLC2A9 Gene Cause Hyperuricosuria and Hyperuricemia in the Dog, PLOS Genetics, 2008
- AAHA — 2014 AAHA Weight Management Guidelines for Dogs and Cats
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIH) — Gout
