Here’s all the latest research on diet and struvite stones/ crystals for dogs, condensed into an easy to read article to help you make the best decision possible for your dog.
What are struvite stones or crystals?
Struvite is the name given to the crystal/ stone that forms in the urinary tract.
Struvite crystals can be present in normal urine and alone, they do not require treatment. However when you combine them with certain bacteria and urine which is too alkaline, this leads to the formation of rock-like formation of minerals that form in the bladder (part of the urinary tract. (1)
As they make their way through the urinary tract, the can cause dog’s serious discomfort and pain.
To understand a little more about how and why they form, you need to understand the urinary tract.
What are the symptoms of a struvite stones in dogs?
- Bloody and/or cloudy urine
- Straining or whimpering during urination
- Accidents in the house
- Needing to be let outside more frequently
- Licking around the urinary opening
- Fever
What does the urinary tract do?
The urinary tract is a waste removal system. When your dog eats, the body takes nutrients from the food and they go into the blood through the digestive process. Not everything taken into the blood is needed or in fact healthy, and some of what the body has used needs removing from the body, the waste. The kidneys and urinary system help the body to eliminate the waste.
Sometimes there’s too much waste or not enough of the right stuff, this creates an environment susceptible to encountering issues, like infections or types of stones or both.
What causes Struvite stones in dogs?
Struvite stones are formed when there are increased levels of bacteria in the urinary tract. Struvite stones are form when there is an overgrowth of bacteria, like Staphylococci and Proteus species, signalling an infection (bacterial imbalance). The bacteria produce the enzyme urease. This enzyme then reacts with urine that’s too alkaline, causing a stone to form. (1)
What are the causes of infection in the Urinary Tract?
Urine Microbiome Imbalance – Incorrect Diet/ Overuse of antibiotics
The urine microbiome is a community of microorganisms (such as bacteria, fungi, and viruses) in the urine, healthy dogs has a diverse bacterial and fungal species. (2)
We used to think that urine was sterile! In fact it contains its own ecosystem of bacteria that comes from the foods that you feed your dog.
Improper functioning of the Lower Urinary Tract – Incorrect diet (mainly) or inherited
The Lower Urinary Tract has several mechanisms for the defence against bacterial overgrowth and imbalance, this includes releasing anti-microbial peptides and releasing neutrophils, immune cells. (3)
Alkaline Urine
A healthy dog produces slightly acidic urine between 6.0-6.5 pH. There is a correlation between bacterial overgrowth with more neutral urine, around pH 7. (4)
Fresh meat is acidic, diets lacking in fresh ingredients, in particular meat and fresh food ingredients become unnaturally alkaline for dogs.
How to treat?
Treatment of your dog’s struvite stones with diet will mean eliminating the underlying causes, to make sure to minimize further damage.
The most important part of ensuring there’s no recurrence, is going to be a move to a fresh food diet. A diverse, balanced bacteria, creating a healthy microbiome, both in the gut and the urine, comes from having a diet with a range of natural fresh foods in the diet.
This will have secondary effects of improving the lower urinary tracts ability to deal with bacterial overgrowth and ensure the urine pH is within the correct range. The use of more acidic ingredients like cranberries or pomegranate can also decrease urine pH effectively. (5)
By using a range of anti-inflammatory ingredients, in combination with a complete diet, your dog will likely not have any recurring issues.
Specific Diet for Struvite Crystals
Protein
A high protein diet is recommended, high in meat to help acidify the urine.
Fats
A standard medium fat diet is recommended.
Carbohydrates
This should be lowered to help balance the gut bacteria and to aid lowering urine pH.
Vitamins and Minerals
A standard complete diet is recommended.
Which supplements are recommended for dogs with Struvite stones or crystals?
Cranberry (6)
D-Mannose (7)
Probiotics (7)
If you’d like more help with your dog’s diet:
For specific Urinary Recipes, click here.
For a consultation call with Cam, click here.
- Lulich, J.P., Berent, A.C., Adams, L.G., Westropp, J.L., Bartges, J.W. and Osborne, C.A., 2019. ACVIM Small Animal Consensus Recommendations on the Treatment and Prevention of Uroliths in Dogs and Cats. 日本獣医腎泌尿器学会誌, 11(1), pp.30-40.
- Melgarejo, T., Oakley, B.B., Krumbeck, J.A., Tang, S., Krantz, A. and Linde, A., 2021. Assessment of bacterial and fungal populations in urine from clinically healthy dogs using next‐generation sequencing. Journal of veterinary internal medicine, 35(3), pp.1416-1426.
- Byron, J.K., 2019. Urinary tract infection. Veterinary Clinics: Small Animal Practice, 49(2), pp.211-221.
- Robin R. Shields-Cutler, Jan R. Crowley, Chia S. Hung, Ann E. Stapleton, Courtney C. Aldrich, Jonas Marschall, Jeffrey P. Henderson. Human Urinary Composition Controls Siderocalin’s Antibacterial Activity. Journal of Biological Chemistry, 2015; jbc.M115.645812 DOI: 1074/jbc.M115.645812
- Chou, H.I., Chen, K.S., Wang, H.C. and Lee, W.M., 2016. Effects of cranberry extract on prevention of urinary tract infection in dogs and on adhesion of Escherichia coli to Madin-Darby canine kidney cells. American journal of veterinary research, 77(4), pp.421-427.
- Chou, H.I., Chen, K.S., Wang, H.C. and Lee, W.M., 2016. Effects of cranberry extract on prevention of urinary tract infection in dogs and on adhesion of Escherichia coli to Madin-Darby canine kidney cells. American journal of veterinary research, 77(4), pp.421-427.
- Gerber, B., 2018. Current tips on the management of canine urinary tract infections.
