Why kittens like to arch their backs:
1. When a cat has abdominal pain, it will arch its back. If the owner finds that the cat has been arching its back for a long time, it needs to take it to the vet for examination in time.
2. If a cat is in a new environment and feels stressed or uncomfortable, it may also arch its back. The owner should comfort the cat in time. 
3. When a cat is frightened and tries to run away, it often arches its back. This is a cat's instinctive reaction.
4. When a cat has just woken up, it likes to arch its back. This is because the cat is stretching its muscles, and it will return to normal after stretching.
5. When a cat sees an insect or a moving object and wants to catch it, it will keep arching its back and chasing it.
