Nutritional management of canine urolithiasis

Urolithiasis is considered to be a common disorder of the urinary tract in dogs (Osborne et al, 2000), with some breeds being more highly represented for certain uroliths than others. Breeds found to be significantly over-represented for calcium oxalate uroliths included the Chihuahua, miniature poodle and Yorkshire terrier. Staffordshire bull terriers and English bulldogs were at increased risk for cystine uroliths (Roe et al, 2012).

Clinical signs of urolithiasis may be the first indication of an underlying systemic disorder, or defect in the structure or function of the urinary tract. As with feline idiopathic cystitis (FIC), urolithiasis should not be viewed as a single disease process, but rather as a sequel of underlying abnormalities. Examination of the urolith composition will aid in determining the aetiology. A full dietary history is required, along with blood serum biochemistry and urinalysis of the concentration of calculogenic mineral, crystallisation promoters and crystallisation inhibitors. Urinary diets for dogs (and cats) can be divided into those that promote dissolution through changing the pH of the urine, and those that act by diluting the concentration of the urine. In all cases, dietary management should only commence once obstruction (if present) has been resolved. The aim of this article is to look at the different nutritional managements that exist for the different canine uroliths that are seen in veterinary practice.