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When was the last moment you smelled something bad? What did you do? For most people, it’s difficult not to flare their nostrils at least. If you’re really tough, you might not have reacted at all. You might have even laughed! Of course, all of these responses are normal. People aren’t the only ones who can respond to smells, good and bad. Your cute cat can sometimes smell what’s going on around them.
You’re not the only one who has seen their cat respond to a smell. Some people have even seen their cat open its mouth and even stick out its tongue while it sniffs, but it’s not clear what this means. Does this happen because of a smell, or is it just a way to get a better smell? No matter what it is, we’re here to find out.
“Why do cats open their mouths when they smell?” is an issue that a lot of people have. We got this information from reliable sources.
When cats smell something, why do they open their mouths?
There are a lot of things that might be confusing when you see your cat open its mouth in a sneering way while it sniffs something. People usually do this when they don’t like the smell, but cats do it to learn more about the smell in the air.
The Flehmen reaction is what this is called. Many cats do this automatically when they smell certain interesting smells, but cats aren’t the only animals that do this. The animal experts at PetMD say that horses, sheep, goats, and even dogs do this. Big cats like tigers and lions also do it. This behaviour has also been seen in rhinos, llamas, giraffes, and other wild animals.
What does the Flehmen say?
Cats open their mouths for a reason, even though it looks like they are making a face expression. The vomeronasal organ, also known as Jacobson’s organ, is an organ in cats that works with hormones and pheromones that are in smells. It is located between the nose and the roof of the mouth. This is what veterinarian Krista Seraydar calls “a combination of taste and smell.” Cats can get this reaction by letting air and its smell go through their mouths and into the Jacobson’s organ. That’s why your cat has their mouth open while sitting next to that stinky sock.
For example, your cat friend might curl their upper lip, stretch their neck, and hold their head high in the air. They might even show their front teeth. Cats may stay in this position with their mouths open for a few seconds while they process the smell. But don’t be surprised if your cat takes a little longer sometimes. It might look like they’re panting, sneering, or even sneezing, but don’t worry—this is all normal.
The Flehmen reaction makes you wonder why cats do it.
Sometimes it seems like cats pick odd times to process the smells and pheromones around them, but the truth is that some smells don’t make them do this. Dr. Seraydar says that the most common things that make domestic cats react to the Flehmen reaction are
- Urine
- Anal gland secretions
- Dirty laundry
- Pheromones from other cats
- New scents
- Anything intriguing
Cats of any gender can use this reaction to find any scent, but male cats usually use it to find female cats that are in heat. Perhaps they want to get a good smell of your friend’s cat, whose scent is on your trousers, or they just can’t leave your bag alone after a trip. Your cat might be interested in smelling anything.
Also, just so you know, the way they look doesn’t mean that your cat thinks these smells are gross or stinky. That’s how they move their face to let air into the Jacobson’s gland. We promise that you shouldn’t be upset if your cat looks down at you after giving you a sniff.
When having your cat’s mouth open might be a bad thing
While the Flehmen reaction is perfectly normal for cats, an open mouth can sometimes be a sign that something is wrong. Cats’ mouths stay open for a short time when they smell something. If their mouth stays open for a long time, you should keep an eye on them. Something might be wrong if you notice things like breathing that doesn’t make sense or panting.
Greencross Vets tells people that cats only pant when they are very hot, very stressed, or sick. Some open-mouth breathing is normal for cats when they are working out or have been outside in warm weather, but cats that pant all the time should be looked at more closely. Greencross Vets says to make sure that your cat’s gums are a healthy pink colour. Take your pet to the vet right away if you see gums that are pale, white, grey, or even blue.
Most of the time, it’s fine for cats to smell with their mouths open. In fact, it’s also pretty helpful. Cats can learn a lot from smells because they contain pheromones and hormones. So don’t worry if you see your cat making a “stinky” face now and then.
