Comforting Traumatized Rescue Animals

At 2 1/2 years old, my male Maltese, Toby, had a calcium-oxalate stone in his bladder and one in his urethra. His vet operated and removed both stones. Toby then was put on a prescription diet food called Urinary SO, manufactured by Royal Canin. Now, two years later, his recent urinalysis came back with crystals.

In addition to the half-cup of Urinary SO, I add two tablespoons of boiled boneless and skinless chicken breast and a tablespoon of poached green beans. For a treat, he gets a tablespoon of dried turkey jerky and a small strip of a dental chew. The Urinary SO's first five ingredients are rice, ground corn, chicken fat, chicken meal and corn-gluten meal.

I feel that something he is eating is contributing to his production of crystals. Should his diet be changed? Also, he is not fond of drinking water.

-- C.M.

via e-mail

Genetic susceptibility and the acidification of the manufactured pet foods that your dog was raised on probably contribute to this difficult-to-prevent situation.

Calcium-oxalate crystals can also be associated with cystitis and bladder infections. But antibiotics should not be given if there are no indications of infection in the dog's urine samples.

Prescription diets, such as the one you describe, are really of dubious scientific and clinical validity, according to some veterinary nutritionists. Also, most animals find them highly unpalatable. Corn and corn gluten have no place in dogs' and cats' diets. Shifting your dog to a partial raw-food diet might help considerably to prevent further crystal formation.