Cat Panting Heavily In Car. Tachypnea is often interchangeable with panting. There are many different reasons a cat may have abnormal breathing.
Cat sleeping phases are divided into alternating phases including rem (rapid eye movement). One of our friends was holding him wrong, and he was let down he starting acting like that. However, if your cat is stressed out, they may show signs of difficulty breathing and wheezing.
Mumcat looks good and is feeding/washing/resting etc, however i am concerned at her 'rapid' breathing which comes and goes.
Then it turned to foaming and then she started to pant very heavily. The cat will breathe with its mouth open in short, rapid bursts. Sometimes cat panting is normal and not a reason to be concerned, especially if you know what kind of activity your cat was involved in immediately beforehand. Cat panting can have many underlying causes.