crystals in cats

Question
My cat has had crystals and I have been told that he has to only eat this special food from the vets called Prescription diet C-D.  My cat didn't eat for 5 days so our vet gave us some pills which should make him feel hungry.  He still didn't eat.  My cat  was very sad and didn't want to do anything, so I gave him some of his fresh meat, which he ate.  What can he eat.  He loves the cheap tuna.  We have tried everything but he still will not eat anything else.  How can we help him from getting crystals when he will only eat the tuna

Answer
Hi.  When you say that he had crystals...are you referring to crystals in his urine/urinary blockage which is commonly referred to as Feline Urologic Syndrome (FUS)?  If so, you definitely need a diet change and need to carefully monitor what he is eating and how much he is drinking.  

Your cat will need to be drinking A LOT of water to flush the urinary tract and maintain a proper urine pH.  He will need a diet that is LOW in Ash (which has been found to contribute to FUS), and LOW in Magnesium.  Always make sure to provide plenty of fresh water...sometimes refilling the bowl to freshen it up several times a day will encourage him to drink more.  It also doesn't hurt to add water to wet food that your cat may be used to eating.  Dry foods generally contain more fiber than canned and semi-moist foods, and fiber draws water as it travels through the bowel, creating more concentrated urine, especially if the cat doesn't drink enough water.  However, dry foods generally have more ash per gram than moist foods, but moist foods alone cannot prevent FUS.  FUS researchers have made a connection between high urinary pH levels and magnesium...which is found in wet foods too.  

The most important thing that you can do is look and compare the ingredients in the foods.  Some cat food manufacturers have supplemented their dry and canned with pH-controlling acidifiers to help to keep the cat's urine pH in the normal range of between 6 and 6.5

I personally feed my cats a combination of dry and canned twice per day, to help balance their moisture intake and minimize high levels of ash, etc.  I have been fortunate enough to never have a cat with FUS.  However, it's sadly become common in cats.  There are several high end brands of food for cats with FUS.  For example, check out http://www.wysong.net/page/WOTTPWS/PROD/URETIC  It is a high quality food and your cat may prefer the flavor to the Prescription c/d...which isn't a high end food and contains a lot of fillers.  I commonly recommend supplementing a diet with raw or cooked chicken, etc.  However, AVOID giving this to your cat, as raw meat contains a high amount of phosphorous and if a cat is known to have urinary problems, phosphorous (in excess) can be harmful to the kidneys.  Also avoid tuna on a regular basis...my cats love it and I offer it to them once every week, sometimes less.  However, tuna does have a high mercury content now, sadly, and the white albacore tuna contains more than the traditional type.  So, be careful not to feed it too often.

My advice is to just check and compare brands.  Go with a high end brand like the Wysong, Wellness, or Nature's Variety and see what he likes.  If he won't eat one, then it certainly won't help him recover because he needs to both eat and drink plenty...he needs to be eating at least twice a day.  You can try not offering food around the clock, but offer it just twice a day and then pick it up after 15 minutes or so, as to encourage him to eat regular meals rather than 'grazing'.  This will also help you monitor just how much he is getting.

So, in a nutshell, when comparing foods, go with LOW Ash, LOW Magnesium, LOW Phosph., and a moderate amount of fiber.  Many vets recommend dry food (because of fiber).  However, just check the labels.  Your cat may prefer a canned diet or a diet of both canned and dry.  Both are totally acceptable if your cat is drinking enough.  If you can't encourage him to increase his water intake, then you can certainly offer chicken broth, add water to canned food, etc.

Hope this info helps!