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Has Your Cat Food Gone Bad? 8 Vet Reviewed Signs to Look For

Vet approved

	Dr. Luqman Javed Photo

Reviewed & Fact-Checked By

Dr. Luqman Javed

DVM (Veterinarian)

The information is current and up-to-date in accordance with the latest veterinarian research.

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The last thing you want to do is feed your cat spoiled food, but you also don’t want to throw it away and waste your money if it’s still good to eat. Because of this, you need to be able to identify spoiled cat food so you don’t accidentally feed it to your cat, and the best way to do this is to look for these common signs of spoiled cat food.

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The 8 Signs That Your Cat Food Has Gone Bad

1. It Looks Weird

Trust your senses. Food can spoil in many ways, and you can often tell just by looking at it. If the food is starting to look funky or just doesn’t look like it normally does, play it safe and don’t feed it to your cat. You wouldn’t want to eat spoiled food, so don’t risk it with your cat either!

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2. It Smells Bad

When something doesn’t smell right, there’s a good chance there’s something wrong with it. However, you need to know what fresh cat food smells like to use this as a test. Because while you might not like the smell of the food, if it’s supposed to smell like that, there might not be anything wrong with it.

owner feeding his cat
Image Credit: Jaromir Chalabala, Shutterstock
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3. It’s Past the Expiration Date

One of the easiest ways to tell if your cat food has gone bad is if it’s past the expiration date. While you can’t assume that the cat food will still be fresh up to the expiration date after you open it, you don’t want to feed it to your cat if it’s after that date.

An important distinction to make here is to know the difference between a “best before” or “best by” date and an expiration date.

A “best before” or “best by” date indicates that the food may still be consumable after it has passed the date, however it may no longer provide the nutrition per the claims on its label.

An expiration date on the other hand means the food is no longer safe to be consumed and should be discarded.

We don’t recommend feeding your cat food when the date has elapsed the “best before”, “best by” or expiration date – even if the food hasn’t gone bad, it will not provide your kitty the nutrition they need for growth, maintenance, or recovery.

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4. There’s Mold

If you see mold in your cat’s food, it’s time to throw it in the trash. There’s no cutting the mold out and serving it to your cat. If mold is forming, all the food needs to go. Mold can cause serious health problems for your cat, and it only starts to form on spoiled food. If the food is in a clear or see through container and appears moldy, do not open the container. Doing so many release fungal spores all around you.

cat food with molds
Image Credit: SOORACHET KHEAWHOM, Shutterstock
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5. The Texture Is Different

When you give your cat their food, you generally have a pretty good idea of how it should feel. If the texture isn’t right, it’s likely spoiled.

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6. Unusual Color

One of the first things that start to change when food spoils is the color. Often, the food will begin to give off more of a gray or green appearance, but no matter the shift in color, it’s time to get rid of it. You know how your cat food should look, so if the color is a bit off, it’s a bad sign.

a fly on dog or cat food
Image Credit: laila63, Shutterstock
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7. It’s Sticky or Slimy

Two ways the texture or look of the food can change if it spoils is it can start to feel sticky or slimy. Sometimes a slimy coating will sit on top of the food, and that’s a sign of spoilage. It depends on what type of cat food you use whether it will become sticky or slimy, but either way, you’ll want to throw it away and get some fresh food for your fur baby.

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8. Your Cat Won’t Eat It

If your cat tends to scarf down their food and all of a sudden won’t touch it, there’s a good chance there’s something wrong with it. It might not taste right to your cat, or it might have an unusual smell.

If your cat is usually a great eater, this is a surefire sign the food is bad. But if your cat is usually a picky eater, that might not be the case. Get to know your cat and you’ll have a better idea of what it means when they’re refusing to eat their food.

Interestingly, cats can taste amino acids (the building blocks of protein) on their food. If your kitty seems exceptionally picky and refuses certain food, check the protein content of the food as it may not be adequate for your kitty.

Cat not eating food
Image Credit: Elena Kutepova, Shutterstock


What To Do If Your Cat Eats Spoiled Food

If you think your cat has ingested something that they shouldn’t (such as food that has gone bad), the best course of action is to take them to a veterinarian right away for a checkup.

It is not advised to wait for signs of digestive distress to develop, as by the time these signs present themselves it means that your cat’s system has been somewhat compromised. Earlier veterinarian intervention offers your cat the best possible prognosis from a food poisoning episode.

Although some cases of digestive upsets are indeed mild, it is always best to err on the side of caution and not gamble with your kitty’s health by “waiting it out” to see how bad they react to something they ate.

Cats are experts at masking pain and illnesses, a kitty that appears apparently healthy after eating spoiled food might just be appearing so instinctively and may crash much worse than a kitty who receives prompt veterinary care.

Your vet can assess your kitty and formulate a stabilization, treatment, and management plan necessary to help your kitty recover if they’ve ingested spoiled food.

bengal cat and vet
Image Credit: Pressmaster, Shutterstock

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While you don’t want to spend more money on cat food than you need to, because of how serious feeding your cat spoiled food can be, you should always play it safe. Don’t feed your cat any food that might be spoiled. Instead, stick with food you know is fresh and safe, even if it means taking an extra trip to the store and spending a bit more.

Your cat is counting on you to feed them food that’s safe to eat, so don’t take any chances with their health!

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Featured Image Credit: Jaromir Chalabala, Shutterstock