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Old December 27th, 2012, 11:27 AM
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sugarcatmom sugarcatmom is offline
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Join Date: May 2007
Location: Calgary, AB
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Hi MPJ!!

Originally Posted by MissPurryJess View Post
I just found out that my 10 year old girl kitty has struvite crystals in her urine. Her pH is about 6 (the vet said it should be 5), but her ultrasound and x-ray showed no stones or "sludge" (as the vet put it).
Was she exhibiting any symptoms that caused you to get the urinalysis, or was it just a routine check-up? Can you get a copy of the results, including the USG?

The presence of crystals is actually quite normal, especially in a sample that has been sitting around for a while as you pointed out. And the vet is way off base about feline urine pH. Normal is 6.0-6.5. A pH of 5.0 is too acidic and increases the risk of calcium oxalate stones developing. PH also fluctuates throughout the day. I personally wouldn't take any diet advice related to an issue that a vet seems to know very little about.

Cutting out the dry food wouldn't be a bad idea, but I see no need to go crazy looking for another wet food at this point. If you want to try adding some variety to your kitties diets, ZiwiPeak makes some great canned foods without any poultry or plant ingredients. Nature's Variety Instinct Venison or Rabbit are also good, and there are some poultry-free Wellness flavours as well (like Beef & Salmon, and I think a couple of the new Core varieties).

Here's more info on urinary tract stuff, with some of the relevant points clipped out:
Crystals are not thought to be a significant cause of cystitis. This is another very common misconception among both lay people and veterinarians leading to, in many cases, inappropriate usage of acidifying prescription diets which can potentially lead to calcium oxylate stones and exacerbate the bladder inflammation.

That said, dietary management must be considered on a case-by-case basis and one-size-fits-all recommendations with respect to diet composition cannot be given. That said, I will give one 'one-size-DOES-fit-all' statement and that is "canned food is always better than dry food due to the appropriate water content in canned foods."
A check for crystals is also not accurate because crystals can form once outside of the bladder in as quickly as 30 minutes. This problem of a 'false positive' can be an issue with urine obtained from a free-catch sample at home, as well as one obtained via cystocentesis that is sent to an outside lab due to the same time delay. If your vet wants to accurately assess for crystals, the urine must be looked at 'in-house' within 30 minutes of cystocentesis or the urine being voided.

pH also may not be accurate in urine samples obtained at home.

A cystocentesis is the best method to obtain urine which will yield the most accurate results.
It is also important to note that diet is not the only factor involved in determining urine pH. The timing of the cat's meals is also a factor. 'Post-prandial alkaline tide' refers to the fact that urine pH will become more alkaline after eating a large meal. Therefore, it is suggest that cats eat multiple small meals throughout the day to help keep the pH in a normal range. Small cats in the wild eat 8-10 small meals per day.

pH can also be affected by certain medications, vomiting, chronic kidney disease, urinary tract infection, diet, stress, and as already discussed, the timing of the last meal.
"To close your eyes will not ease another's pain." ~ Chinese Proverb

“We must not refuse to see with our eyes what they must endure with their bodies.” ~ Gretchen Wyler
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