Bladder stones can be a recurring nightmare for our furry friends. The clinical signs of bladder stones, different types of stones, and causes on stone formation were discussed in the previous Before the Bowl Blog “Part 1: Guide to bladder stones in dogs”. But did you know that nutrition can make a world of difference? In this blog post you will learn about dietary strategies that can help to prevent bladder stones from re-occurring, and how to support your dog’s urinary health.
The Role of Water Intake in Urolith Formation
Encouraging consumption of water is an essential factor in minimizing the occurrence of all types of bladder stones in dogs. Water helps to dilute the urine and increase urine flow – both of which are helpful in preventing stone formation. Tips and methods to encourage water consumption for your dog can be found in more detail in our previous blog post “Beat the Heat: Your Guide to Pet Hydration.” Most common strategies are to feed wet or fresh food or to add water to dry food. Increased sodium chloride content is also a strategy often applied for urinary health diets, as this helps to increase thirst and encourage water intake, resulting in a larger volume of more dilute urine.
Dietary Treatment and Prevention for Uroliths
Dietary treatment options mainly depend on the types and composition of the stone(s), as well as the overall health of the dog. Dietary prevention focuses on reducing intake of the nutrients that promote urolith formation.
Struvite
Struvite stones can be treated with purposely-formulated veterinary therapeutic diets that are typically low in phosphorus and magnesium. In certain instances, these diets may also feature reduced protein content, contributing to the reduction of urea and acidifying the urine to a pH of less than 6.5. Thus, these diets are specially formulated to dissolve the struvite stones. Vitamin C should not be supplemented when struvite treatment diets are fed.
To prevent struvite stone recurrence, acidifying foods with mild to moderately reduced levels of protein, magnesium and phosphorus are recommended. Additionally, increasing water intake is recommended by either adding water to dry food or feeding canned food to prevent the formation of struvite stones.
Calcium Oxalate
Unfortunately, successful dietary treatment for calcium oxalate stones has not been reported in dogs. At present, only physical techniques, such as surgery, are accessible for eliminating calcium oxalate uroliths. However, dietary management plays a role in preventing the recurrence of these stones.
Dietary prevention methods include increasing water intake and avoiding ingestion of foods that contain high quantities of animal protein since they may contribute to the formation of calcium oxalate urolithiasis. Excessive intake of calcium and oxalic acid, as well as the supplementation of vitamin C should be avoided.
| Human foods to be restricted for dogs with calcium oxalate uroliths | Human foods okay to feed | ||
| Limited | Avoid | Low calcium | Low oxalate |
| Oysters Herring Spinach Tofu Asparagus Carrots Corn Lettuce Oranges Peaches Pineapple | Salmon Broccoli Cheese Milk Yogurt Celery Cucumber Eggplant Most berries Peanuts | Eggs Poultry Almonds Macaroni Pretzels Rice Spaghetti Walnuts | Beef Eggs Lamb Pork Poultry Cabbage Cauliflower Mushrooms Apples Noodles Rice |
Urate
Treatment for dogs with urate stones includes increasing water intake and feeding a low-protein, low-purine diet.
To prevent urate urolith formation, foods that are restricted in purine should be considered. Furthermore, high protein foods should be avoided.
| Foods to avoid (high purine content) | Foods to limit or restrict (moderate to high purine content) | Foods okay to feed (low purine content) |
| Anchovies Clams Goose Gravies Heart Kidney Liver Mackerel Mussels Oysters Salmon Scallops Shrimp Tuna | Asparagus Cauliflower Legumes (beans and peas) Meats Mushroom Spinach | Breads (whole grain cereal products) Butter and fats Cheese Eggs Fruits Milk Nuts Sugars Vegetable soups Creams Most vegetables (except those in second column) |
Cystine
Veterinary therapeutic diets that are low in protein and sodium are often recommended to dissolve cystine stones.
To prevent the recurrence of cystine uroliths, high protein diets, particularly high-protein dry diets abundant in methionine. Apart from meats, other food ingredients high in methionine include eggs, wheat, and peanuts. Lowering dietary protein intake has the potential to reduce the formation of cystine.
Currently, there are no established dietary protocols proven to effectively dissolve canine silica stones. Surgery remains the only practical option for the removal of large silica uroliths.
The quantity and types of protein play a crucial role in managing the formation of silica uroliths in dogs. It is recommended to implement moderate protein restriction. While animal-derived protein ingredients are an unlikely source of silica, foods containing large amounts of plant-derived ingredients such as corn gluten feed, rice hulls, and soybean hulls pose a risk for silica uroliths in dogs.
In summary
The treatment and prevention of different types of uroliths in dogs depend on the creation of individualized feeding plans. These plans should be tailored to the dog’s specific needs, the type of stones they are prone to, and their overall health condition. It is crucial to consult with veterinarians to select the best diets and feeding strategies that can effectively treat and prevent the formation of stones. Regular check-ups and monitoring are also essential to ensure the dietary plan’s effectiveness and make necessary adjustments. Remember, every dog is unique, and their nutritional needs may vary, making personalized care vital in maintaining their health and well-being.
Always consult with your veterinarians to choose the best dietary strategy to prevent stone formations in your dogs.
Written by:
Kehan (Coco) Zhang, BScH, MSc
Alison Ng, BScH, OVC Class of 2027
Reviewed by:
Dr. Erico Ribeiro, DVM, MSc, PhD, DVSc Candidate, ECVCN Resident
Dr. Sarah K. Abood, DVM, PhD, Associate Professor, Nestlé Purina Professorship in Companion Animal Nutrition
Dr. Adronie Verbrugghe, DVM, PhD, Dip ECVCN, Associate Professor and Royal Canin Veterinary Diets Endowed Chair in Canine and Feline Clinical Nutrition
References
Lulich, J. P., Berent, A. C., Adams, L. G., Westropp, J. L., Bartges, J. W., & Osborne, C. A. (2016). ACVIM Small Animal Consensus Recommendations on the Treatment and Prevention of Uroliths in Dogs and Cats. Journal of veterinary internal medicine, 30(5), 1564–1574. https://doi.org/10.1111/jvim.14559
Osborne, C.A., Bartges, J. W., Lulich, J. P. (2000). Canine Urolithiasis. In: Hand. M. S., Thatcher, C. D., Remillard, R. L., Roudebush, P (Eds.), Small animal clinical nutrition 4th edition. Missouri: Mark Morris Institute. https://www.markmorrisinstitute.org/sacn5_download.html