What Does a Low Concentration in a Canine Urine Test Mean?

Drinking from the toilet can dilute a dog's urine.
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Urine testing's a standard element for many senior dogs, dogs on long-term medications and those with urinary concerns. A crucial part of urinalysis, the specific gravity test tells your veterinarian how concentrated your dog’s urine is. A low specific gravity indicates your dog is losing too much water through his urine.


Your dog’s kidneys perform several crucial functions. One of the most important is regulating his body’s fluid balance. A low urine specific gravity reading often means your dog’s kidneys are not retaining enough water to prevent dehydration. Essentially, fluids flow too freely through and out of his body. Your vet uses a tool called a refractometer to measure the urine's gravity, which is essentially the density of the urine relative to the mass of an equal volume of water. On average, any canine specific gravity reading lower than 1.030 is considered too low. Several medical conditions, such as kidney disease, adrenal gland disease and diabetes, can cause diluted urine.


Though illness is often associated with low urine concentration, many other factors can affect the measurement. Increased water intake and infrequent urinalysis have the potential to produce inaccurate readings. One test is not enough to confirm illness; your vet will likely collect urine for testing throughout the day to create a spectrum, as well as order blood work, X-rays or ultrasound if needed for definitive diagnosis.