Diet for Dogs With Struvite Crystals

Confined dogs may not urinate often enough to prevent urinary infections.
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Many dogs have struvite crystals in their urine, which does not necessarily indicate a medical condition. The crystals, composed of magnesium, ammonium and phosphate, become a problem only if your dog contracts a urinary tract infection. The changes caused in the crystals by a staphylococcal or Proteus infection from the gastrointestinal tract results in the formation of struvite bladder stones, which can cause the dog discomfort. If left untreated, bladder stones can result in serious illness and death.


Restricted urination is one of the main causes of a urinary infection that can convert struvite crystals into bladder stones and is usually a result of confinement, an insufficient water intake and a lack of regular exercise. Hydration is an important part of the diet for dogs whose urine has tested positive for struvite crystals. Ensure that your dog drinks enough water daily by adding salt to the diet to increase her thirst; give her the chance to urinate frequently. The additional water intake also dilutes the urine, reducing the concentration of minerals.

Dietary Needs

Feed the dog a diet that is easily digestible and has a low fiber content. This helps to prevent the loss of fluids from the intestines through absorption by the fiber. Homemade dog food should include cooked rice, oil, and small quantities of high-quality protein such as eggs or tuna. For example, combine 3 cups of cooked rice with 2 large boiled eggs and 1 tablespoon of canola oil. Avoid using meat byproducts instead of real meat. Most adult dogs will readily accept commercially available foods such as Hill’s Prescription Diet Canine s/d brand or Royal Canin’s Urinary SO diet.


Several nutritional supplements have proved effective in diluting the urine of dogs. Vitamin C is known for its acidic content, which changes the pH balance of the urine, creating an acidic environment that is less conducive to transformation of crystals into stones. Capsules of concentrated cranberry extract help stop bacteria from adhering to the walls of the bladder and the urinary tract, which can cause urinary infections. A variety of probiotics formulated specifically for dogs helps keep the bacteria in the urinary tract healthy, preventing infections.

Changing the Diet

A dog with struvite crystals should not be on a special diet for extended periods. Diet should be used to reduce the risk of developing bladder stones only when advised by your veterinarian, usually when the dog is potentially predisposed to them through certain risk factors. Female dogs are at greater risk of contracting the disease and make up 85 percent of canine bladder stone patients. Dogs that have previously had stones treated or surgically removed have a risk of recurrent infection, and certain breeds are particularly susceptible to the condition. When changing the dog's diet, mix small quantities of the new food with the dog’s regular food, gradually increasing until only the new food is given. Test the urine regularly for crystals, and once they disappear, migrate the dog slowly back onto regular food.



About the Author

Tracey Sandilands has written professionally since 1990, covering business, home ownership and pets. She holds a professional business management qualification, a bachelor's degree in communications and a diploma in public relations and journalism. Sandilands is the former editor of an international property news portal and an experienced dog breeder and trainer.

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