Many cats, especially those that are overweight, may breath more noisily or heavier when sleeping. Many even snore. If she is breathing normally during the rest of her day and shows no difficulty breathing after play, she is most likely just fine. If you are concerned though, you could have your veterinarian take a quick listen to her lungs to make sure she is ok now. If you don’t take her in now, be sure to mention it at your next visit.
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