Hi all,
My beloved 16 year old female cat was just diagnosed with CRF. Luckily, we think we caught it pretty early. My vet thinks that my feeding her Prescription C/D for the past 10 years contributed to the kidney problems because C/D is too "acidic" for a long term food.

So I've switched my kitty to a high-quality protein moist food now (Wellness turkey). But I have two other younger cats that I still like to feed dry food to (they don't care for moist believe it or not). So just in case my kidney-kitty eats a few kibbles of dry food, I was thinking of getting a low-phosphorous dry food for my other 2 cats. But how do I know when a fairly low-phosphorous dry food is also not too acidic? After all, according to the below link, C/D is fairly low in phosphorous and yet it's supposedly too acidic. Well, what about something like Hill's Nature's Best chicken formula dry food? It is listed as being fairly low in phosphorous but is it also too acidic and thus harmful to kidneys?
http://binkyspage.tripod.com/dryfood.html
Thanks!
Brad
Hi all, My beloved 16 year old female cat was just diagnosed with CRF. Luckily, we think we caught it ... as being fairly low in phosphorous but is it also too acidic and thus harmful to kidneys? http://binkyspage.tripod.com/dryfood.html Thanks! Brad

Wellness canned is an excellent food. Just be sure to get the grain free* varieties such as chicken, turkey, and beef. It would be much better to eliminate all dry food for *all of your kitties. You might also want to try Innova EVO 95%. Cats are obligate carnivores. They do not need and should not have the type of carbs found in all dry food. There are various problems, in addition to what you already mentioned. For example, nearly all cats with diabetes are cats that have been fed dry food. Yes, I realize your kitties prefer dry food now because they have been used to it, but you can gradually transition them.
MaryL
But how do I know when a fairly low-phosphorous dry food is
also not too acidic?

The easiest way would be to call Hill's and ask them what the target urine pH is for the diet in which you're interested.. Hill's used to include that information in the typical analyses of all their diets on their website.

Looking at the ingredients list, I would say Nature's Best Chicken Formula is acidified and probably produces a urine pH of 6.1 to 6.3- much lower than you want. DL-Methionine is listed in the ingredients list and is used as a urinary acidifier in cat foods. Cranberries, citric acid, and corn gluten meal also acidify the urine. Digest, which is used to enhance palatability of dry food is either sprayed on the outside or incorporated directly into the food can also acidify urine.
All commercial cat foods- especially dry foods- were reformulated about 15 years ago to produce an acidic urine to reduce the incidence of struvite crystals. I think you're going to be hard-pressed to find an OTC cat diet that isn't acidified.
You might want to look into buying a good pH meter. I have a Hanna pH Checker and recommend it highly. It only costs about $30.

Best of luck,
Phil