Calabrò, S. et al.
2011
The British Journal of Nutrition

This randomized controlled trial performed with twelve adult dogs diagnosed with stuvite urolithiasis, the effect of two commercially available dry foods for the management of the disease were compared. The key difference amongst both foods analysed was the anion-cation balance difference on urinary pH. For the design of the study, the subjects were divided into two groups (diet A and diet B, both with a negative anion-cation balance of -203 and -192, respectively) and fed the corresponding diet for a period of three months. During this time, urinalysis were repeated six times for each dog.
In the first urinalysis, the pH values ​​of all dogs were nearly 8.0, and bacteria were present in approximately 70%, therefore an antimicrobial was administered to all dogs for 1 week. The recommended pH values ​​for stone dissolution were reached after two months and it was achieved progressively. From the sampling at day 30, group A which had a lower negative anion-cation balance showed significantly lower values than group B. However, the combined management through antimicrobial and diet resulted effective in both groups achieving the dissolution of struvite uroliths. Diet A, however, seemed to decrease the urinary pH faster, and therefore in looking out for the animal's wellbeing and avoiding the risk of other diseases, the discontinuation of this dietary approach would be recommended.