Comparison chart: Urolithiasis diets for dogs

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Rock climbing: good. Rock 'n' roll: good. Pop Rocks: very good.

Bladder rocks: not so good.

And the cats!

You can check out our comparison chart for feline urolithiasis diets at dvm360.com/caturolithdiets.

When mineral crystals in a dog's urine aggregate to form uroliths, they can become large enough to cause hematuria, dysuria and even partial or full obstruction of the urinary tract.

Though the exact mechanisms behind urolithiasis are not yet completely understood in dogs (or cats, for that matter), these two factors are a must: sufficiently high urine concentrations of the substances that form uroliths, and slower movement of crystals within the urinary tract.1 The development of some stones is also affected by factors like diet, genetics, infection and medications.1

Though diet can be a contributing factor in stone formation, it can also be part of treatment and prevention. Knowing a urolith's chemical composition is key. The most common canine uroliths include:

Struvite (magnesium ammonium phosphate): Struvite stones top the list of common canine uroliths and are typically caused by urinary tract infections. They are the only stones that can be completely dissolved via therapeutic diet.

Calcium oxalate: Calcium oxalate stones can develop in any breed, though miniature schnauzers, Lhasa apsos, Yorkshire terriers, bichons frisés, shih tzus and miniature poodles may be predisposed.1

Urate: Ammonium urate stones are most frequently found in Dalmatians and in dogs with congenital portosystemic vascular shunts.1

The therapeutic diets in the chart below are formulated to address at least one of these types of stones, and three of them also list the prevention of a less common type of stone-cystine-as a benefit.

Despite their differences, all of the diets have at least two things in common: the need for thorough client communication and regular follow-up appointments. Explain to clients that extra food (rawhides, table scraps, treats, supplements) could thwart the diet's effectiveness. Be explicit regarding what their dog can (and can't) have between meals and why. Don't be bashful about revisiting this topic during follow-up appointments as you monitor your patient's response to the diet-especially if the food doesn't have the effect you expected.

(Editor's note: The chart on the next page isn't exhaustive. These manufacturers produce other diets that include sterile struvite and calcium oxalate stone prevention benefits. The diets included on the chart are those that have the urinary tract as their main focus.)

Therapeutic urolithiasis diets for dogs

Information chart

Food

Struvite dissolution?

Struvite prevention?

Calcium oxalate prevention?

Cystine prevention?

Urate prevention?

Calories

Guaranteed analysis

Link to website and other info

Dry foods

Blue Buffalo Natural Veterinary Diet W+U Weight Management + Urinary Care

YES

YES

309 per cup

• Crude protein: 30% min

• Crude fat: 10% min

• Crude fiber: 17% max

• Moisture: 10% max

• Calcium: 1% min

• Phosphorus: 0.7% min

• Magnesium: 0.14% max

• Sodium: 0.15% min, 0.35% max

• Vitamin E: 300 IU/kg min

• Soluble fiber: 1% min

• Taurine: 0.2% min

• Omega 3 fatty acids: 0.5% min

• Omega 6 fatty acids: 2% min

• L-carnitine: 250 mg/kg min

bluebuffalo.com/natural-dog-food/blue-natural-veterinary-diet/wu-dry-food-for-dogs

Hill's Prescription Diet c/d Urinary Care Multicare Canine

YES

YES

YES

375 per cup

• Crude protein: 18% min

• Crude fat: 13% min, 18% max

• Crude fiber: 5% max

• Calcium: 0.45% min, 0.9% max

• Phosphorus: 0.41% min, 0.7% max

• Sodium: 0.3% max

• Magnesium: 0.06% min, 0.12% max

• Omega 3 fatty acids: 0.45% min

hillspet.com/dog-food/pd-cd-multicare-canine-dry

Hill's Prescription Diet Metabolic + Urinary Canine

YES

YES

279 per cup

• Crude protein: 21% min

• Crude fat: 8.5% min

• Crude fiber: 16% max

• Crude moisture: 10% max

• Calcium: 0.3% min, 0.9% max

• Magnesium: 0.06% min, 0.09% max

• Omega 3 fatty acids: 0.45% min

hillspet.com/dog-food/pd-metabolic-plus-urinary-canine-dry

Hill's Prescription Diet Urinary Care u/d Canine

YES

YES

398 per cup

• Crude protein: 8% min, 12% max

• Crude fat: 17.5% min

• Crude fiber: 3% max

• Calcium: 0.45% max

• Sodium: 0.3% max

• Taurine: 0.09% min

• Vitamin E: 400 IU/kg min

• Carnitine: 150 ppm min

hillspet.com/dog-food/pd-ud-canine-dry#

Purina Pro Plan Veterinary Diets UR Urinary Ox/St Canine Formula

YES

YES

YES

408 per cup

• Crude protein: 21% min

• Crude fat: 9% min

• Crude fiber: 6.5% max

• Moisture: 12% max

• Ash: 8.5% max

• Calcium: 0.9% min

• Phosphorus: 0.7% min

proplanveterinarydiets.com/products/ur-urinary-oxst-dog

Royal Canin Canine Urinary UC Dry Dog Food

YES

YES

339 per cup

• Crude protein: 18% min

• Crude fat: 13% min

• Crude fiber: 3% max

• Moisture: 10% max

• Methionine-cystine: 0.74% min

royalcanin.com/us/dogs/products/vet-products/canine-urinary-uc-low-purine-dry-dog-food

Royal Canin Canine Urinary SO Dry Dog Food

YES

YES

YES

333 per cup

• Crude protein: 14% min

• Crude fat: 14% min

• Crude fiber: 4.7% max

• Moisture: 10% max

• Magnesium: 0.08% max

royalcanin.com/us/dogs/products/vet-products/canine-urinary-so-dry-dog-food

Small dog, moderate calorie, satiety and hydrolyzed protein formulas also available.

Wet foods

Blue Buffalo Natural Veterinary Diet W+U Weight Management + Urinary Care

YES

YES

312 per 12.5-oz can

• Crude protein: 7.5% min

• Crude fat: 2.5% min

• Crude fiber: 5% max

• Moisture: 78% max

• Vitamin E: 50 IU/kg min

• Ascorbic acid: 20 mg/kg min

• L-carnitine: 60 mg/kg min

bluebuffalo.com/natural-dog-food/blue-natural-veterinary-diet/wu-wet-food-for-dogs/

Hill's Prescription Diet Urinary Care c/d Multicare Canine Chicken Flavor

YES

YES

YES

463 per 13-oz can

• Crude protein: 5.5% min

• Crude fat: 4% min

• Crude fiber: 2% max

hillspet.com/dog-food/pd-cd-multicare-canine-canned

Chicken-and-vegetable-stew flavor also available

Hill's Prescription Diet Urinary Care s/d Canine

YES

(dissolves in as little as 6 days; average 13 days)

YES

468 per 13-oz can

• Crude protein: 2% min

• Crude fat: 6% min

• Crude fiber: 1% max

• Moisture: 72% max

hillspet.com/dog-food/pd-sd-canine-canned#

Hill's Prescription Diet u/d Canine

YES

YES

499 per 13-oz can

• Crude protein: 2% min

• Crude fat: 5% min

• Crude fiber: 1% max

• Moisture: 74% max

https://www.hillspet.com/dog-food/pd-ud-canine-canned

Purina Pro Plan Veterinary Diets UR Urinary Ox/St

Canine Formula

YES

YES

YES

392 per 13.3-oz can

• Crude protein: 7.5% min

• Crude fat: 4.5% min

• Crude fiber: 3% max

• Moisture: 78% max

• Ash: 2.25% max

• Calcium: 0.16% min

• Phosphorus: 0.15% min

• Magnesium: 0.04% max

proplanvetdirect.com/ur-urinary-ox-st

Royal Canin Canine Urinary SO Loaf Canned Dog Food

YES

YES

YES

478 per 13.5-oz can

• Crude protein: 5.6% min

• Crude fat: 5.9% min

• Crude fiber: 2.1% max

• Moisture: 73.5% max

royalcanin.com/us/dogs/products/vet-products/canine-urinary-so-in-gel-canned-dog-food

Moderate calorie formula also available

Source: Manufacturers' packaging and marketing materials

Reference

1. Brown SA. Merck Veterinary Manual. Urolithiasis in small animals. Available at: merckvetmanual.com/urinary-system/noninfectious-diseases-of-the-urinary-system-in-small-animals/urolithiasis-in-small-animals. Accessed Sep 11, 2019.

Sarah Mouton Dowdy, a former associate content specialist for dvm360.com, is a freelance writer and editor in Kansas City, Missouri.