The reasons why a cat bites as soon as its belly is touched:
1. It is a normal conditioned reflex of cats. If a cat is petted on its belly while it is sleeping, the cat will form a conditioned reflex and will immediately bite the owner's hand.
2. The cat’s belly is the most sensitive part of the cat. If the cat feels that the environment it is in is unsafe, it will attack if its sensitive parts are touched.
3. Cats like to bite their owners. If the owner often likes to use his hands to tease the cat, then the cat will like to bite your hand, so when you put a hand on its belly, then Thought you were playing with it.

4. Cats feel uncomfortable when you touch them, so they will bite you when you touch them.

Signs of a cat not trusting its owner:

1. It resists being touched by its owner. As soon as the owner reaches out to touch it, it will run away, or its hair will stand on end, making an aggressive gesture. And opened his mouth to roar.

2. Singing against the master, disobeying the master’s instructions and going his own way.

3. Never lick the owner, never actively seek caressing, and never act coquettishly.

4. Being very alert when sleeping at home, waking up immediately when there is any movement, or hiding to sleep are all signs of insecurity and distrust.

5. Protect your food. Cats are very vigilant when eating.

6. There are often signs of airplane ears, or tail drooping, or tail between legs.