Why is my cat purring with its mouth open when purring heavily?

This is perfectly normal. Some cats have a tiny quiet purr, others a very loud purr, and others again actually open their mouth a little to purr loudly. The louder your kitty purrs the happier it is. Hairballs usually cause a cough. Sounds like you have a very happy kitty.

Thank you for submitting your question regarding Kida. I recommend that she sees a veterinarian. Respiratory issues can be very serious. If she is breathing with her mouth open at all, then you need to seek emergency care right away as this indicates respiratory distress. I hope this information helps!

As long as she isn't in any distress and seems comfortable, that may just be her purring. However, if this is a behavior you've never seen in her before, it's worth getting her checked by your vet just to make sure she doesn't have the start of an upper respiratory infection or something similar.

That may be due to a pharyngeal/laryngeal inflammation, potentially due to a viral or bacterial infection. A check up would be needed to have a look inside his mouth and throat and spot any sign of it. Antibiotics may be needed.

Breathing more heavily than normal is often an early sign of illness in cats, so I would definitely encourage you to take Prince to the vet for a check up as soon as you are able to. Often, we see this in cats with heart disease, fluid in the chest cavity, or even certain types of cancer. They may not show any other symptoms of a problem until their illness gets much worse, so it's always best to have this checked sooner rather than later. Your vet can listen to Prince's heart and lungs to check for any obvious abnormalities, and may also recommend chest x-rays to look for some of the problems I mentioned above.

Thank you for submitting your question regarding Kopol. That is odd behavior for a cat to display. Is he tasting something bad during these episodes? A new food for example? If not, does he pant or breathe with his mouth open? This can be a sign of respiratory distress in a cat. I recommend that he sees his veterinarian for an examination. He could possibly be painful. Based on these results, blood work may be recommended as well. A thyroid disorder can cause a cat to meow more frequently. I hope this information helps!

There can be multiple causes for a cat to have its mouth open, though that is abnormal behavior. Cats are obligatory nasal breathers, so any panting or open mouthed breathing can be a sign of respiratory distress (heart or lung disease). It can also be secondary to dental disease or nerve damage. I would recommend Zazu be evaluated by his regular veterinarian to determine the underlying cause for his issue, any diagnostics (X-rays, bloodwork), and any treatment if needed. Good luck!