The reasons why a kitten opens its mouth to pant without opening its eyes:

1. Panting with its mouth open is caused by being too hot or exercising too much. It is recommended to drink more water.

2. It may be because the big cat is suppressing it, causing difficulty in breathing. Just open the big cat.

3. The kitten may be sick and has difficulty breathing. It needs to go to the hospital for examination and treatment as soon as possible.

4. It may be that the kitten’s body functions have declined, which is a sign that it is about to die.