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Is it weird that I’m thinking about your cat’s bladder?

If it doesn’t bother you, it doesn’t bother me. And, well, let’s be honest, even if it makes you a little squeamish that I’m pondering your cat’s bladder, I’m not going to stop. Because, frankly, I’m fascinated.

We hear about quite a few cases of urinary crystals, specifically Struvite and Oxalate crystals, in the store. So, being an obsessive cat owner, I started researching what all this “crystal” talk was about.

What kind of healthy diet can help a cat’s urinary health if they have, or are prone to crystals? What ARE Struvite and Oxalate crystals? What sort of diet can cause or exacerbate crystals?

I focused on diet because not only is that the best way we at the store can help you, but also because I find that many issues begin and end with what your pet is eating.

So here are my findings:

(NOTE: I focused on cats because the majority of crystals cases we encounter involve cats, but much of the information — especially pertaining to diet– is applicable to dogs as well. When in doubt, as your vet!)

What are Struvite and Oxalate Crystals?

Struvite and Oxalate crystals are two types of urinary tract crystals that can form in a cat’s bladder or urinary tract. You may also hear the title Feline Urinary Tract Disease or FLUTD, to describe this, which is a blanket statement that describes ailments in that region.

Struvite crystals are a combination of minerals — magnesium, ammonium and phosphorus. Struvite crystals tend to form in an urinary tract environment that has a higher pH, or a more alkaline environment. Struvite crystals cannot form in a more acidic environment, so in order to treat Struvite crystals, a cat’s urine pH should be lowered, or made more acidic.

Oxalate crystals are calcium based. Oxalate crystals form when the urinary tract environment of a cat is too acidic. In previous generations, Oxalate crystals were far less common than Struvite crystals, but because Struvite crystals became so common, cat food companies began acidifying their foods more, thus stopping the formation of Struvite crystals, but creating a hospitable environment for Oxalate crystals.

Oxalate crystals are harder to treat than Struvite crystals. Surgery or an expulsion procedure is usually needed.

My cat has crystals! How should I alter their diet?

Find a cat food with an appropriate pH. If your cat has/had Oxalate crystals, find a food that is more alkaline. If you cat has/had Struvite crystals, find a food that is more acidic. THERE HAS TO BE A BALANCE! Don’t go too overboard on highly acidic or alkaline foods, you may end up resolving one crystal and encouraging another.

Contact your cat’s food manufacturer to find out the pH of the food, most reputable companies should be willing and able to tell you!

Most of what I’ve encountered encourages altering the pH of a cat’s urine (starting with the food) in order to treat or recover from crystals. There is some thought that in cases of Struvite crystals, magnesium levels should be lowered too, by feeding a food low in magnesium. However, it seems lowering the acidity of the cat’s urine seems to be a more effective way to combat crystals.

In some cases, lowering the magnesium too much in a cat’s food, or lowering the “ash” level (which is just a blanket term for minerals in cat food, it is not actually ash like we’d think from a campfire!), can predispose a cat to Oxalate crystals. Just like people, every cat should be treated on a case by case basis as to what is the best course of action for them.

I’ll say it again, when in doubt, ask your vet!

What kind of food should I feed my cat if he or she has/had crystals?

Hydrate, hydrate, hydrate! Cats who are habitually dehydrated, or only eat dry food are for more likely to form crystals!

Keep several clean water sources available for your cat around your house. Cats in general never drink enough water, so encouraging your cat to drink is something you can start doing now!

Try to avoid dry food completely. Your cat will do much better on a wet diet, even a raw diet, but if you must feed your cat kibble, soak it in water. Keep your cat’s food as close to it’s “natural diet” as possible, that way the optimal pH will be maintained in their urinary tract, around 6.3.

Cat’s are obligate carnivores, so feeding them an “unnatural” diet high in carbohydrates, grains, or plant protein, can also contribute to crystals forming. Keeping them on a high moisture, meat based diet is an excellent preventative measure that most owners can take to insure their cat’s urinary tract health.

And, yes, I know feeding raw or wet food can be more expensive than feeding kibble, but when you think about how much vet visits, medication, even surgery — not to mention the comfort and stress level of your cat — can cost if your cat gets FLUTD, paying more for wet or raw food now, will save you money in the future.

Warning signs your cat (or DOG too! this can happen to dogs too!) has a potentially fatal blockage and should be taken to the vet immediately

Note that not all crystals are life threatening. Sometimes they can pass on their own, or with some vet and owner intervention. However, sometimes a crystal can go unchecked, and the results can be life threatening. This is especially true in male cats, as they have narrower urethras.

If your cat exhibits a few of the following symptoms, get them to a vet as soon as possible. It is possible for a cat to die within 48 hours of a blockage forming.

  • straining to urinate, with no urine production

  • odd walking, “bow legged”

  • crying, intensifies when picked up

  • pain upon handling

  • not eating

  • vomiting

  • strange, depressed, behavior

ME-OW! Who would have thought such tiny little things like crystals could cause so many issues!

But rest assured, that if your cat is currently healthy, by feeding them a meat based diet, with access to lots of water, you can hopefully avoid urinary crystals in the future.

Give your kitty a scratch for us!

~Your Loyal Calvin & Susie Blogger

As always, check with your vet before making any changes to your pet’s diet or body care. The Calvin & Susie Blogger always researches to the best of her ability, but she is not a vet. This blog is not in any way meant to replace veterinary advice or care. When in doubt always ask a vet.

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