Lab value · USG
Urine Specific Gravity in cats, explained
USG shows how concentrated the urine is. Healthy cat kidneys make very concentrated urine; kidneys with CKD lose that ability.
What a higher urine specific gravity can mean
A higher USG means more concentrated urine — generally a sign the kidneys can still conserve water.
What a lower urine specific gravity can mean
A lower USG means more dilute urine. In cats, values below about 1.035 are often an early clue of reduced kidney function (other causes exist too).
Why it matters in kidney disease
- Losing the ability to concentrate urine is often one of the earliest signs of CKD in cats.
- Healthy cats usually produce urine above about 1.035. In CKD it is often lower, sometimes close to 1.008–1.012, which is about the concentration of blood plasma itself.
- USG has to be read alongside blood values. Diet, fluids and some medicines can change it.
Questions to ask your vet
Ask your vet
- Is my cat’s urine concentration consistent with CKD?
- Should we check a urine culture?
Decode your cat’s USG
Enter your cat’s values and get a plain-English summary, IRIS reference bars and questions for your vet.
Frequently asked questions
What is Urine Specific Gravity in a cat blood test?
USG shows how concentrated the urine is. Healthy cat kidneys make very concentrated urine; kidneys with CKD lose that ability.
What does a high urine specific gravity mean in cats?
A higher USG means more concentrated urine — generally a sign the kidneys can still conserve water.
What does a low urine specific gravity mean in cats?
A lower USG means more dilute urine. In cats, values below about 1.035 are often an early clue of reduced kidney function (other causes exist too).
What is a normal urine specific gravity level for a cat?
A typical feline reference interval is about Example only: 1.035 – 1.060. Use the range printed on your cat’s report — it differs between labs., but every lab sets its own range. The range printed on your cat’s report is the one to use.
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