Dog urinary stones: what are we talking about?
Urinary stones are also called urolithiasis or urolithiasis. These are small agglomerates, most often minerals, whose size can vary from a grain of sand to a small pebble and which form in the dog's urinary tract.
You can find it in the kidneys, ureter, bladder or urethra.
These calculations can be of different nature and be formed:
- calcium oxalate,
- ammoniac-magnesium phosphate (or struvites),
- calcium phosphate,
- of cystine,
- xanthine,
- urates.
In dogs, struvite and calcium oxalate stones are the most common.
What causes stones to appear in dogs?
The causes of the appearance of calculations in dogs are numerous and variable depending on the nature of these calculations.
But, overall, we can say that the calculations are formed thanks to a hypersaturation of the urine in minerals or in another substance (cystine, xanthine), which can be favored by a poor quality diet, an excessive concentration of urine (if the animal does not drink enough or has been administered diuretics), a porto-systemic shunt or a metabolic disorder which may be of genetic origin. For this last reason, some dog breeds are genetically predisposed to developing certain types of stones.This is for example the case of the Dalmatian with ammonium urate stones.
The formation of stones is also often dependent on urinary pH, whether it is either acidic or too alkaline, which can also be influenced by the dog's diet (among other factors).
Overweight and physical inactivity are also risk factors for the appearance of urinary stones in dogs because they promote urine stagnation by reducing the number of urinations.
Chronic urinary tract infections can also be a contributing factor, especially in the formation of struvite stones.
What are the symptoms of urinary stones in dogs?
Symptoms related to the presence of urinary stones vary depending on the location of the stones within the urinary tract.
So if your dog suffers from kidney stones, it may manifest as:
- abdominal pain,
- signs of kidney failure,
- haematuria (presence of blood in the urine),
- fever in case of associated pyelonephritis.
If the stones are located in the bladder, we can observe:
- a pollakiuria (very frequent urge to urinate),
- dysuria (difficulty urinating normally),
- blood in urine,
- and urinary incontinence.
To these symptoms, we must add signs of acute renal failure, an absence of emission of urine which then accumulates in the bladder, making it painful (we then speak of a bladder globe) and a strong dejection if the stones are in the urethra, the channel that allows urine to evacuate from the bladder to the outside of the body, through the urinary meatus.
It also happens that urethral stones (or urethroliths) completely block the entrance to the penis in male dogs, which constitutes an absolute emergency situation.
What treatments for urinary stones in dogs?
When the calculations do not cause urinary obstruction and do not jeopardize the animal's short-term vital prognosis, the veterinarian will endeavor to put in place a medical and dietary treatment which will purpose of dissolving calculations. This treatment may be accompanied by antibiotic treatment when the stones are associated with a urinary tract infection.
He can also try to eliminate bladder stones using the urohydropulsion technique. It consists of exerting manual pressure on the full bladder in order to expel the stones and requires sedation or general anesthesia of the animal.
In the absence of response to medical and dietary treatment or in an emergency, the stones will then be removed surgically.
If the formation of stones is secondary to hypercalcemia or liver disease, the causes will be sought by the veterinarian to be treated as well.
Urinary stones and dog food
In general, to avoid the recurrence of urinary stones or to help them dissolve, the lifestyle and dietary treatment of stones consists of:
Reduce your dog's urinary density
Increase urine volume by increasing water consumption. Indeed, the minerals dissolved in the urine will have less chance of “precipitating” and forming stones if they are less concentrated. The strategy to adopt? Prefer wet food to dry food and encourage your dog to drink more by:
- changing the water in his bowl several times a day,
- using a water fountain,
- placing several bowls in different rooms of your home,
- giving him spring water, which is more attractive than tap water because it is not chlorinated (but be careful: no mineral water!) or letting the tap water settle for at least 24 hours before give it to your pet,
- using ceramic bowls rather than plastic bowls to better preserve the freshness of drinking water.
Administer a specific diet
In general, a specific diet helps to obtain a urinary pH that minimizes the formation of stones and reduces the dietary intake of minerals.
Specifically dogs with stones:
- of calcium oxalate should receive a diet low in protein, with reduced intakes of calcium, oxalate and sodium and acidifying urine,
- ammoniac-magnesium phosphate (or struvites): restricted in magnesium, phosphorus and protein and acidifying the urine,
- calcium phosphate: a food low in protein, calcium and vitamin D,
- of cystine: low in protein and s alt and alkalizing the urine,
- xanthine: food low in purine and alkalinizing urine,
- urates: food low in protein and purine, rich in water and alkalizing urine.
In order to limit variations in urinary pH, your pet's meals should ideally be distributed to him in several times rather than all at once. Also remember to make your dog move more to limit the stagnation of his urine.